File size: 59,055 Bytes
f998fcd
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
// This contract is part of Zellic’s smart contract dataset, which is a collection of publicly available contract code gathered as of March 2023.

// File: @openzeppelin/contracts/utils/Counters.sol


// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)

pragma solidity ^0.8.0;

/**

 * @title Counters

 * @author Matt Condon (@shrugs)

 * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number

 * of elements in a mapping, issuing ERC721 ids, or counting request ids.

 *

 * Include with `using Counters for Counters.Counter;`

 */
library Counters {
    struct Counter {
        // This variable should never be directly accessed by users of the library: interactions must be restricted to
        // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
        // this feature: see https://github.com/ethereum/solidity/issues/4637
        uint256 _value; // default: 0
    }

    function current(Counter storage counter) internal view returns (uint256) {
        return counter._value;
    }

    function increment(Counter storage counter) internal {
        unchecked {
            counter._value += 1;
        }
    }

    function decrement(Counter storage counter) internal {
        uint256 value = counter._value;
        require(value > 0, "Counter: decrement overflow");
        unchecked {
            counter._value = value - 1;
        }
    }

    function reset(Counter storage counter) internal {
        counter._value = 0;
    }
}

// File: @openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol


// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)

pragma solidity ^0.8.0;

/**

 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in

 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].

 *

 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by

 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't

 * need to send a transaction, and thus is not required to hold Ether at all.

 */
interface IERC20Permit {
    /**

     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,

     * given ``owner``'s signed approval.

     *

     * IMPORTANT: The same issues {IERC20-approve} has related to transaction

     * ordering also apply here.

     *

     * Emits an {Approval} event.

     *

     * Requirements:

     *

     * - `spender` cannot be the zero address.

     * - `deadline` must be a timestamp in the future.

     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`

     * over the EIP712-formatted function arguments.

     * - the signature must use ``owner``'s current nonce (see {nonces}).

     *

     * For more information on the signature format, see the

     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP

     * section].

     */
    function permit(

        address owner,

        address spender,

        uint256 value,

        uint256 deadline,

        uint8 v,

        bytes32 r,

        bytes32 s

    ) external;

    /**

     * @dev Returns the current nonce for `owner`. This value must be

     * included whenever a signature is generated for {permit}.

     *

     * Every successful call to {permit} increases ``owner``'s nonce by one. This

     * prevents a signature from being used multiple times.

     */
    function nonces(address owner) external view returns (uint256);

    /**

     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.

     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// File: @openzeppelin/contracts/utils/introspection/IERC165.sol


// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)

pragma solidity ^0.8.0;

/**

 * @dev Interface of the ERC165 standard, as defined in the

 * https://eips.ethereum.org/EIPS/eip-165[EIP].

 *

 * Implementers can declare support of contract interfaces, which can then be

 * queried by others ({ERC165Checker}).

 *

 * For an implementation, see {ERC165}.

 */
interface IERC165 {
    /**

     * @dev Returns true if this contract implements the interface defined by

     * `interfaceId`. See the corresponding

     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]

     * to learn more about how these ids are created.

     *

     * This function call must use less than 30 000 gas.

     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// File: @openzeppelin/contracts/utils/introspection/ERC165.sol


// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)

pragma solidity ^0.8.0;


/**

 * @dev Implementation of the {IERC165} interface.

 *

 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check

 * for the additional interface id that will be supported. For example:

 *

 * ```solidity

 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {

 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);

 * }

 * ```

 *

 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.

 */
abstract contract ERC165 is IERC165 {
    /**

     * @dev See {IERC165-supportsInterface}.

     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

// File: @openzeppelin/contracts/utils/Strings.sol


// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)

pragma solidity ^0.8.0;

/**

 * @dev String operations.

 */
library Strings {
    bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
    uint8 private constant _ADDRESS_LENGTH = 20;

    /**

     * @dev Converts a `uint256` to its ASCII `string` decimal representation.

     */
    function toString(uint256 value) internal pure returns (string memory) {
        // Inspired by OraclizeAPI's implementation - MIT licence
        // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol

        if (value == 0) {
            return "0";
        }
        uint256 temp = value;
        uint256 digits;
        while (temp != 0) {
            digits++;
            temp /= 10;
        }
        bytes memory buffer = new bytes(digits);
        while (value != 0) {
            digits -= 1;
            buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
            value /= 10;
        }
        return string(buffer);
    }

    /**

     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.

     */
    function toHexString(uint256 value) internal pure returns (string memory) {
        if (value == 0) {
            return "0x00";
        }
        uint256 temp = value;
        uint256 length = 0;
        while (temp != 0) {
            length++;
            temp >>= 8;
        }
        return toHexString(value, length);
    }

    /**

     * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.

     */
    function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
        bytes memory buffer = new bytes(2 * length + 2);
        buffer[0] = "0";
        buffer[1] = "x";
        for (uint256 i = 2 * length + 1; i > 1; --i) {
            buffer[i] = _HEX_SYMBOLS[value & 0xf];
            value >>= 4;
        }
        require(value == 0, "Strings: hex length insufficient");
        return string(buffer);
    }

    /**

     * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.

     */
    function toHexString(address addr) internal pure returns (string memory) {
        return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
    }
}

// File: @openzeppelin/contracts/utils/cryptography/ECDSA.sol


// OpenZeppelin Contracts (last updated v4.7.3) (utils/cryptography/ECDSA.sol)

pragma solidity ^0.8.0;


/**

 * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.

 *

 * These functions can be used to verify that a message was signed by the holder

 * of the private keys of a given address.

 */
library ECDSA {
    enum RecoverError {
        NoError,
        InvalidSignature,
        InvalidSignatureLength,
        InvalidSignatureS,
        InvalidSignatureV
    }

    function _throwError(RecoverError error) private pure {
        if (error == RecoverError.NoError) {
            return; // no error: do nothing
        } else if (error == RecoverError.InvalidSignature) {
            revert("ECDSA: invalid signature");
        } else if (error == RecoverError.InvalidSignatureLength) {
            revert("ECDSA: invalid signature length");
        } else if (error == RecoverError.InvalidSignatureS) {
            revert("ECDSA: invalid signature 's' value");
        } else if (error == RecoverError.InvalidSignatureV) {
            revert("ECDSA: invalid signature 'v' value");
        }
    }

    /**

     * @dev Returns the address that signed a hashed message (`hash`) with

     * `signature` or error string. This address can then be used for verification purposes.

     *

     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:

     * this function rejects them by requiring the `s` value to be in the lower

     * half order, and the `v` value to be either 27 or 28.

     *

     * IMPORTANT: `hash` _must_ be the result of a hash operation for the

     * verification to be secure: it is possible to craft signatures that

     * recover to arbitrary addresses for non-hashed data. A safe way to ensure

     * this is by receiving a hash of the original message (which may otherwise

     * be too long), and then calling {toEthSignedMessageHash} on it.

     *

     * Documentation for signature generation:

     * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]

     * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]

     *

     * _Available since v4.3._

     */
    function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
        if (signature.length == 65) {
            bytes32 r;
            bytes32 s;
            uint8 v;
            // ecrecover takes the signature parameters, and the only way to get them
            // currently is to use assembly.
            /// @solidity memory-safe-assembly
            assembly {
                r := mload(add(signature, 0x20))
                s := mload(add(signature, 0x40))
                v := byte(0, mload(add(signature, 0x60)))
            }
            return tryRecover(hash, v, r, s);
        } else {
            return (address(0), RecoverError.InvalidSignatureLength);
        }
    }

    /**

     * @dev Returns the address that signed a hashed message (`hash`) with

     * `signature`. This address can then be used for verification purposes.

     *

     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:

     * this function rejects them by requiring the `s` value to be in the lower

     * half order, and the `v` value to be either 27 or 28.

     *

     * IMPORTANT: `hash` _must_ be the result of a hash operation for the

     * verification to be secure: it is possible to craft signatures that

     * recover to arbitrary addresses for non-hashed data. A safe way to ensure

     * this is by receiving a hash of the original message (which may otherwise

     * be too long), and then calling {toEthSignedMessageHash} on it.

     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, signature);
        _throwError(error);
        return recovered;
    }

    /**

     * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.

     *

     * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]

     *

     * _Available since v4.3._

     */
    function tryRecover(

        bytes32 hash,

        bytes32 r,

        bytes32 vs

    ) internal pure returns (address, RecoverError) {
        bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
        uint8 v = uint8((uint256(vs) >> 255) + 27);
        return tryRecover(hash, v, r, s);
    }

    /**

     * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.

     *

     * _Available since v4.2._

     */
    function recover(

        bytes32 hash,

        bytes32 r,

        bytes32 vs

    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, r, vs);
        _throwError(error);
        return recovered;
    }

    /**

     * @dev Overload of {ECDSA-tryRecover} that receives the `v`,

     * `r` and `s` signature fields separately.

     *

     * _Available since v4.3._

     */
    function tryRecover(

        bytes32 hash,

        uint8 v,

        bytes32 r,

        bytes32 s

    ) internal pure returns (address, RecoverError) {
        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return (address(0), RecoverError.InvalidSignatureS);
        }
        if (v != 27 && v != 28) {
            return (address(0), RecoverError.InvalidSignatureV);
        }

        // If the signature is valid (and not malleable), return the signer address
        address signer = ecrecover(hash, v, r, s);
        if (signer == address(0)) {
            return (address(0), RecoverError.InvalidSignature);
        }

        return (signer, RecoverError.NoError);
    }

    /**

     * @dev Overload of {ECDSA-recover} that receives the `v`,

     * `r` and `s` signature fields separately.

     */
    function recover(

        bytes32 hash,

        uint8 v,

        bytes32 r,

        bytes32 s

    ) internal pure returns (address) {
        (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
        _throwError(error);
        return recovered;
    }

    /**

     * @dev Returns an Ethereum Signed Message, created from a `hash`. This

     * produces hash corresponding to the one signed with the

     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]

     * JSON-RPC method as part of EIP-191.

     *

     * See {recover}.

     */
    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
        // 32 is the length in bytes of hash,
        // enforced by the type signature above
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
    }

    /**

     * @dev Returns an Ethereum Signed Message, created from `s`. This

     * produces hash corresponding to the one signed with the

     * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]

     * JSON-RPC method as part of EIP-191.

     *

     * See {recover}.

     */
    function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
    }

    /**

     * @dev Returns an Ethereum Signed Typed Data, created from a

     * `domainSeparator` and a `structHash`. This produces hash corresponding

     * to the one signed with the

     * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]

     * JSON-RPC method as part of EIP-712.

     *

     * See {recover}.

     */
    function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
    }
}

// File: @openzeppelin/contracts/utils/cryptography/draft-EIP712.sol


// OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol)

pragma solidity ^0.8.0;


/**

 * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.

 *

 * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,

 * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding

 * they need in their contracts using a combination of `abi.encode` and `keccak256`.

 *

 * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding

 * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA

 * ({_hashTypedDataV4}).

 *

 * The implementation of the domain separator was designed to be as efficient as possible while still properly updating

 * the chain id to protect against replay attacks on an eventual fork of the chain.

 *

 * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method

 * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].

 *

 * _Available since v3.4._

 */
abstract contract EIP712 {
    /* solhint-disable var-name-mixedcase */
    // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
    // invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
    uint256 private immutable _CACHED_CHAIN_ID;
    address private immutable _CACHED_THIS;

    bytes32 private immutable _HASHED_NAME;
    bytes32 private immutable _HASHED_VERSION;
    bytes32 private immutable _TYPE_HASH;

    /* solhint-enable var-name-mixedcase */

    /**

     * @dev Initializes the domain separator and parameter caches.

     *

     * The meaning of `name` and `version` is specified in

     * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:

     *

     * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.

     * - `version`: the current major version of the signing domain.

     *

     * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart

     * contract upgrade].

     */
    constructor(string memory name, string memory version) {
        bytes32 hashedName = keccak256(bytes(name));
        bytes32 hashedVersion = keccak256(bytes(version));
        bytes32 typeHash = keccak256(
            "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
        );
        _HASHED_NAME = hashedName;
        _HASHED_VERSION = hashedVersion;
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
        _CACHED_THIS = address(this);
        _TYPE_HASH = typeHash;
    }

    /**

     * @dev Returns the domain separator for the current chain.

     */
    function _domainSeparatorV4() internal view returns (bytes32) {
        if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
            return _CACHED_DOMAIN_SEPARATOR;
        } else {
            return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
        }
    }

    function _buildDomainSeparator(

        bytes32 typeHash,

        bytes32 nameHash,

        bytes32 versionHash

    ) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
    }

    /**

     * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this

     * function returns the hash of the fully encoded EIP712 message for this domain.

     *

     * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:

     *

     * ```solidity

     * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(

     *     keccak256("Mail(address to,string contents)"),

     *     mailTo,

     *     keccak256(bytes(mailContents))

     * )));

     * address signer = ECDSA.recover(digest, signature);

     * ```

     */
    function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
        return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
    }
}

// File: @openzeppelin/contracts/access/IAccessControl.sol


// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)

pragma solidity ^0.8.0;

/**

 * @dev External interface of AccessControl declared to support ERC165 detection.

 */
interface IAccessControl {
    /**

     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`

     *

     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite

     * {RoleAdminChanged} not being emitted signaling this.

     *

     * _Available since v3.1._

     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**

     * @dev Emitted when `account` is granted `role`.

     *

     * `sender` is the account that originated the contract call, an admin role

     * bearer except when using {AccessControl-_setupRole}.

     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**

     * @dev Emitted when `account` is revoked `role`.

     *

     * `sender` is the account that originated the contract call:

     *   - if using `revokeRole`, it is the admin role bearer

     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)

     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**

     * @dev Returns `true` if `account` has been granted `role`.

     */
    function hasRole(bytes32 role, address account) external view returns (bool);

    /**

     * @dev Returns the admin role that controls `role`. See {grantRole} and

     * {revokeRole}.

     *

     * To change a role's admin, use {AccessControl-_setRoleAdmin}.

     */
    function getRoleAdmin(bytes32 role) external view returns (bytes32);

    /**

     * @dev Grants `role` to `account`.

     *

     * If `account` had not been already granted `role`, emits a {RoleGranted}

     * event.

     *

     * Requirements:

     *

     * - the caller must have ``role``'s admin role.

     */
    function grantRole(bytes32 role, address account) external;

    /**

     * @dev Revokes `role` from `account`.

     *

     * If `account` had been granted `role`, emits a {RoleRevoked} event.

     *

     * Requirements:

     *

     * - the caller must have ``role``'s admin role.

     */
    function revokeRole(bytes32 role, address account) external;

    /**

     * @dev Revokes `role` from the calling account.

     *

     * Roles are often managed via {grantRole} and {revokeRole}: this function's

     * purpose is to provide a mechanism for accounts to lose their privileges

     * if they are compromised (such as when a trusted device is misplaced).

     *

     * If the calling account had been granted `role`, emits a {RoleRevoked}

     * event.

     *

     * Requirements:

     *

     * - the caller must be `account`.

     */
    function renounceRole(bytes32 role, address account) external;
}

// File: @openzeppelin/contracts/utils/Context.sol


// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

pragma solidity ^0.8.0;

/**

 * @dev Provides information about the current execution context, including the

 * sender of the transaction and its data. While these are generally available

 * via msg.sender and msg.data, they should not be accessed in such a direct

 * manner, since when dealing with meta-transactions the account sending and

 * paying for execution may not be the actual sender (as far as an application

 * is concerned).

 *

 * This contract is only required for intermediate, library-like contracts.

 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: @openzeppelin/contracts/access/AccessControl.sol


// OpenZeppelin Contracts (last updated v4.7.0) (access/AccessControl.sol)

pragma solidity ^0.8.0;





/**

 * @dev Contract module that allows children to implement role-based access

 * control mechanisms. This is a lightweight version that doesn't allow enumerating role

 * members except through off-chain means by accessing the contract event logs. Some

 * applications may benefit from on-chain enumerability, for those cases see

 * {AccessControlEnumerable}.

 *

 * Roles are referred to by their `bytes32` identifier. These should be exposed

 * in the external API and be unique. The best way to achieve this is by

 * using `public constant` hash digests:

 *

 * ```

 * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");

 * ```

 *

 * Roles can be used to represent a set of permissions. To restrict access to a

 * function call, use {hasRole}:

 *

 * ```

 * function foo() public {

 *     require(hasRole(MY_ROLE, msg.sender));

 *     ...

 * }

 * ```

 *

 * Roles can be granted and revoked dynamically via the {grantRole} and

 * {revokeRole} functions. Each role has an associated admin role, and only

 * accounts that have a role's admin role can call {grantRole} and {revokeRole}.

 *

 * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means

 * that only accounts with this role will be able to grant or revoke other

 * roles. More complex role relationships can be created by using

 * {_setRoleAdmin}.

 *

 * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to

 * grant and revoke this role. Extra precautions should be taken to secure

 * accounts that have been granted it.

 */
abstract contract AccessControl is Context, IAccessControl, ERC165 {
    struct RoleData {
        mapping(address => bool) members;
        bytes32 adminRole;
    }

    mapping(bytes32 => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /**

     * @dev Modifier that checks that an account has a specific role. Reverts

     * with a standardized message including the required role.

     *

     * The format of the revert reason is given by the following regular expression:

     *

     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/

     *

     * _Available since v4.1._

     */
    modifier onlyRole(bytes32 role) {
        _checkRole(role);
        _;
    }

    /**

     * @dev See {IERC165-supportsInterface}.

     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
    }

    /**

     * @dev Returns `true` if `account` has been granted `role`.

     */
    function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
        return _roles[role].members[account];
    }

    /**

     * @dev Revert with a standard message if `_msgSender()` is missing `role`.

     * Overriding this function changes the behavior of the {onlyRole} modifier.

     *

     * Format of the revert message is described in {_checkRole}.

     *

     * _Available since v4.6._

     */
    function _checkRole(bytes32 role) internal view virtual {
        _checkRole(role, _msgSender());
    }

    /**

     * @dev Revert with a standard message if `account` is missing `role`.

     *

     * The format of the revert reason is given by the following regular expression:

     *

     *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/

     */
    function _checkRole(bytes32 role, address account) internal view virtual {
        if (!hasRole(role, account)) {
            revert(
                string(
                    abi.encodePacked(
                        "AccessControl: account ",
                        Strings.toHexString(uint160(account), 20),
                        " is missing role ",
                        Strings.toHexString(uint256(role), 32)
                    )
                )
            );
        }
    }

    /**

     * @dev Returns the admin role that controls `role`. See {grantRole} and

     * {revokeRole}.

     *

     * To change a role's admin, use {_setRoleAdmin}.

     */
    function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
        return _roles[role].adminRole;
    }

    /**

     * @dev Grants `role` to `account`.

     *

     * If `account` had not been already granted `role`, emits a {RoleGranted}

     * event.

     *

     * Requirements:

     *

     * - the caller must have ``role``'s admin role.

     *

     * May emit a {RoleGranted} event.

     */
    function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
        _grantRole(role, account);
    }

    /**

     * @dev Revokes `role` from `account`.

     *

     * If `account` had been granted `role`, emits a {RoleRevoked} event.

     *

     * Requirements:

     *

     * - the caller must have ``role``'s admin role.

     *

     * May emit a {RoleRevoked} event.

     */
    function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
        _revokeRole(role, account);
    }

    /**

     * @dev Revokes `role` from the calling account.

     *

     * Roles are often managed via {grantRole} and {revokeRole}: this function's

     * purpose is to provide a mechanism for accounts to lose their privileges

     * if they are compromised (such as when a trusted device is misplaced).

     *

     * If the calling account had been revoked `role`, emits a {RoleRevoked}

     * event.

     *

     * Requirements:

     *

     * - the caller must be `account`.

     *

     * May emit a {RoleRevoked} event.

     */
    function renounceRole(bytes32 role, address account) public virtual override {
        require(account == _msgSender(), "AccessControl: can only renounce roles for self");

        _revokeRole(role, account);
    }

    /**

     * @dev Grants `role` to `account`.

     *

     * If `account` had not been already granted `role`, emits a {RoleGranted}

     * event. Note that unlike {grantRole}, this function doesn't perform any

     * checks on the calling account.

     *

     * May emit a {RoleGranted} event.

     *

     * [WARNING]

     * ====

     * This function should only be called from the constructor when setting

     * up the initial roles for the system.

     *

     * Using this function in any other way is effectively circumventing the admin

     * system imposed by {AccessControl}.

     * ====

     *

     * NOTE: This function is deprecated in favor of {_grantRole}.

     */
    function _setupRole(bytes32 role, address account) internal virtual {
        _grantRole(role, account);
    }

    /**

     * @dev Sets `adminRole` as ``role``'s admin role.

     *

     * Emits a {RoleAdminChanged} event.

     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        bytes32 previousAdminRole = getRoleAdmin(role);
        _roles[role].adminRole = adminRole;
        emit RoleAdminChanged(role, previousAdminRole, adminRole);
    }

    /**

     * @dev Grants `role` to `account`.

     *

     * Internal function without access restriction.

     *

     * May emit a {RoleGranted} event.

     */
    function _grantRole(bytes32 role, address account) internal virtual {
        if (!hasRole(role, account)) {
            _roles[role].members[account] = true;
            emit RoleGranted(role, account, _msgSender());
        }
    }

    /**

     * @dev Revokes `role` from `account`.

     *

     * Internal function without access restriction.

     *

     * May emit a {RoleRevoked} event.

     */
    function _revokeRole(bytes32 role, address account) internal virtual {
        if (hasRole(role, account)) {
            _roles[role].members[account] = false;
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

// File: @openzeppelin/contracts/security/Pausable.sol


// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)

pragma solidity ^0.8.0;


/**

 * @dev Contract module which allows children to implement an emergency stop

 * mechanism that can be triggered by an authorized account.

 *

 * This module is used through inheritance. It will make available the

 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to

 * the functions of your contract. Note that they will not be pausable by

 * simply including this module, only once the modifiers are put in place.

 */
abstract contract Pausable is Context {
    /**

     * @dev Emitted when the pause is triggered by `account`.

     */
    event Paused(address account);

    /**

     * @dev Emitted when the pause is lifted by `account`.

     */
    event Unpaused(address account);

    bool private _paused;

    /**

     * @dev Initializes the contract in unpaused state.

     */
    constructor() {
        _paused = false;
    }

    /**

     * @dev Modifier to make a function callable only when the contract is not paused.

     *

     * Requirements:

     *

     * - The contract must not be paused.

     */
    modifier whenNotPaused() {
        _requireNotPaused();
        _;
    }

    /**

     * @dev Modifier to make a function callable only when the contract is paused.

     *

     * Requirements:

     *

     * - The contract must be paused.

     */
    modifier whenPaused() {
        _requirePaused();
        _;
    }

    /**

     * @dev Returns true if the contract is paused, and false otherwise.

     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**

     * @dev Throws if the contract is paused.

     */
    function _requireNotPaused() internal view virtual {
        require(!paused(), "Pausable: paused");
    }

    /**

     * @dev Throws if the contract is not paused.

     */
    function _requirePaused() internal view virtual {
        require(paused(), "Pausable: not paused");
    }

    /**

     * @dev Triggers stopped state.

     *

     * Requirements:

     *

     * - The contract must not be paused.

     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**

     * @dev Returns to normal state.

     *

     * Requirements:

     *

     * - The contract must be paused.

     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol


// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**

 * @dev Interface of the ERC20 standard as defined in the EIP.

 */
interface IERC20 {
    /**

     * @dev Emitted when `value` tokens are moved from one account (`from`) to

     * another (`to`).

     *

     * Note that `value` may be zero.

     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**

     * @dev Emitted when the allowance of a `spender` for an `owner` is set by

     * a call to {approve}. `value` is the new allowance.

     */
    event Approval(address indexed owner, address indexed spender, uint256 value);

    /**

     * @dev Returns the amount of tokens in existence.

     */
    function totalSupply() external view returns (uint256);

    /**

     * @dev Returns the amount of tokens owned by `account`.

     */
    function balanceOf(address account) external view returns (uint256);

    /**

     * @dev Moves `amount` tokens from the caller's account to `to`.

     *

     * Returns a boolean value indicating whether the operation succeeded.

     *

     * Emits a {Transfer} event.

     */
    function transfer(address to, uint256 amount) external returns (bool);

    /**

     * @dev Returns the remaining number of tokens that `spender` will be

     * allowed to spend on behalf of `owner` through {transferFrom}. This is

     * zero by default.

     *

     * This value changes when {approve} or {transferFrom} are called.

     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**

     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.

     *

     * Returns a boolean value indicating whether the operation succeeded.

     *

     * IMPORTANT: Beware that changing an allowance with this method brings the risk

     * that someone may use both the old and the new allowance by unfortunate

     * transaction ordering. One possible solution to mitigate this race

     * condition is to first reduce the spender's allowance to 0 and set the

     * desired value afterwards:

     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729

     *

     * Emits an {Approval} event.

     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**

     * @dev Moves `amount` tokens from `from` to `to` using the

     * allowance mechanism. `amount` is then deducted from the caller's

     * allowance.

     *

     * Returns a boolean value indicating whether the operation succeeded.

     *

     * Emits a {Transfer} event.

     */
    function transferFrom(

        address from,

        address to,

        uint256 amount

    ) external returns (bool);
}

// File: @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol


// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)

pragma solidity ^0.8.0;


/**

 * @dev Interface for the optional metadata functions from the ERC20 standard.

 *

 * _Available since v4.1._

 */
interface IERC20Metadata is IERC20 {
    /**

     * @dev Returns the name of the token.

     */
    function name() external view returns (string memory);

    /**

     * @dev Returns the symbol of the token.

     */
    function symbol() external view returns (string memory);

    /**

     * @dev Returns the decimals places of the token.

     */
    function decimals() external view returns (uint8);
}

// File: @openzeppelin/contracts/token/ERC20/ERC20.sol


// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;




/**

 * @dev Implementation of the {IERC20} interface.

 *

 * This implementation is agnostic to the way tokens are created. This means

 * that a supply mechanism has to be added in a derived contract using {_mint}.

 * For a generic mechanism see {ERC20PresetMinterPauser}.

 *

 * TIP: For a detailed writeup see our guide

 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How

 * to implement supply mechanisms].

 *

 * We have followed general OpenZeppelin Contracts guidelines: functions revert

 * instead returning `false` on failure. This behavior is nonetheless

 * conventional and does not conflict with the expectations of ERC20

 * applications.

 *

 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.

 * This allows applications to reconstruct the allowance for all accounts just

 * by listening to said events. Other implementations of the EIP may not emit

 * these events, as it isn't required by the specification.

 *

 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}

 * functions have been added to mitigate the well-known issues around setting

 * allowances. See {IERC20-approve}.

 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    /**

     * @dev Sets the values for {name} and {symbol}.

     *

     * The default value of {decimals} is 18. To select a different value for

     * {decimals} you should overload it.

     *

     * All two of these values are immutable: they can only be set once during

     * construction.

     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    /**

     * @dev Returns the name of the token.

     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }

    /**

     * @dev Returns the symbol of the token, usually a shorter version of the

     * name.

     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    /**

     * @dev Returns the number of decimals used to get its user representation.

     * For example, if `decimals` equals `2`, a balance of `505` tokens should

     * be displayed to a user as `5.05` (`505 / 10 ** 2`).

     *

     * Tokens usually opt for a value of 18, imitating the relationship between

     * Ether and Wei. This is the value {ERC20} uses, unless this function is

     * overridden;

     *

     * NOTE: This information is only used for _display_ purposes: it in

     * no way affects any of the arithmetic of the contract, including

     * {IERC20-balanceOf} and {IERC20-transfer}.

     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    /**

     * @dev See {IERC20-totalSupply}.

     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**

     * @dev See {IERC20-balanceOf}.

     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**

     * @dev See {IERC20-transfer}.

     *

     * Requirements:

     *

     * - `to` cannot be the zero address.

     * - the caller must have a balance of at least `amount`.

     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

    /**

     * @dev See {IERC20-allowance}.

     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**

     * @dev See {IERC20-approve}.

     *

     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on

     * `transferFrom`. This is semantically equivalent to an infinite approval.

     *

     * Requirements:

     *

     * - `spender` cannot be the zero address.

     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

    /**

     * @dev See {IERC20-transferFrom}.

     *

     * Emits an {Approval} event indicating the updated allowance. This is not

     * required by the EIP. See the note at the beginning of {ERC20}.

     *

     * NOTE: Does not update the allowance if the current allowance

     * is the maximum `uint256`.

     *

     * Requirements:

     *

     * - `from` and `to` cannot be the zero address.

     * - `from` must have a balance of at least `amount`.

     * - the caller must have allowance for ``from``'s tokens of at least

     * `amount`.

     */
    function transferFrom(

        address from,

        address to,

        uint256 amount

    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }

    /**

     * @dev Atomically increases the allowance granted to `spender` by the caller.

     *

     * This is an alternative to {approve} that can be used as a mitigation for

     * problems described in {IERC20-approve}.

     *

     * Emits an {Approval} event indicating the updated allowance.

     *

     * Requirements:

     *

     * - `spender` cannot be the zero address.

     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

    /**

     * @dev Atomically decreases the allowance granted to `spender` by the caller.

     *

     * This is an alternative to {approve} that can be used as a mitigation for

     * problems described in {IERC20-approve}.

     *

     * Emits an {Approval} event indicating the updated allowance.

     *

     * Requirements:

     *

     * - `spender` cannot be the zero address.

     * - `spender` must have allowance for the caller of at least

     * `subtractedValue`.

     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    /**

     * @dev Moves `amount` of tokens from `from` to `to`.

     *

     * This internal function is equivalent to {transfer}, and can be used to

     * e.g. implement automatic token fees, slashing mechanisms, etc.

     *

     * Emits a {Transfer} event.

     *

     * Requirements:

     *

     * - `from` cannot be the zero address.

     * - `to` cannot be the zero address.

     * - `from` must have a balance of at least `amount`.

     */
    function _transfer(

        address from,

        address to,

        uint256 amount

    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(from, to, amount);

        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing

     * the total supply.

     *

     * Emits a {Transfer} event with `from` set to the zero address.

     *

     * Requirements:

     *

     * - `account` cannot be the zero address.

     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

    /**

     * @dev Destroys `amount` tokens from `account`, reducing the

     * total supply.

     *

     * Emits a {Transfer} event with `to` set to the zero address.

     *

     * Requirements:

     *

     * - `account` cannot be the zero address.

     * - `account` must have at least `amount` tokens.

     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

    /**

     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.

     *

     * This internal function is equivalent to `approve`, and can be used to

     * e.g. set automatic allowances for certain subsystems, etc.

     *

     * Emits an {Approval} event.

     *

     * Requirements:

     *

     * - `owner` cannot be the zero address.

     * - `spender` cannot be the zero address.

     */
    function _approve(

        address owner,

        address spender,

        uint256 amount

    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**

     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.

     *

     * Does not update the allowance amount in case of infinite allowance.

     * Revert if not enough allowance is available.

     *

     * Might emit an {Approval} event.

     */
    function _spendAllowance(

        address owner,

        address spender,

        uint256 amount

    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }

    /**

     * @dev Hook that is called before any transfer of tokens. This includes

     * minting and burning.

     *

     * Calling conditions:

     *

     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens

     * will be transferred to `to`.

     * - when `from` is zero, `amount` tokens will be minted for `to`.

     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.

     * - `from` and `to` are never both zero.

     *

     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].

     */
    function _beforeTokenTransfer(

        address from,

        address to,

        uint256 amount

    ) internal virtual {}

    /**

     * @dev Hook that is called after any transfer of tokens. This includes

     * minting and burning.

     *

     * Calling conditions:

     *

     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens

     * has been transferred to `to`.

     * - when `from` is zero, `amount` tokens have been minted for `to`.

     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.

     * - `from` and `to` are never both zero.

     *

     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].

     */
    function _afterTokenTransfer(

        address from,

        address to,

        uint256 amount

    ) internal virtual {}
}

// File: @openzeppelin/contracts/token/ERC20/extensions/draft-ERC20Permit.sol


// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/extensions/draft-ERC20Permit.sol)

pragma solidity ^0.8.0;






/**

 * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in

 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].

 *

 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by

 * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't

 * need to send a transaction, and thus is not required to hold Ether at all.

 *

 * _Available since v3.4._

 */
abstract contract ERC20Permit is ERC20, IERC20Permit, EIP712 {
    using Counters for Counters.Counter;

    mapping(address => Counters.Counter) private _nonces;

    // solhint-disable-next-line var-name-mixedcase
    bytes32 private constant _PERMIT_TYPEHASH =
        keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    /**

     * @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.

     * However, to ensure consistency with the upgradeable transpiler, we will continue

     * to reserve a slot.

     * @custom:oz-renamed-from _PERMIT_TYPEHASH

     */
    // solhint-disable-next-line var-name-mixedcase
    bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;

    /**

     * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.

     *

     * It's a good idea to use the same `name` that is defined as the ERC20 token name.

     */
    constructor(string memory name) EIP712(name, "1") {}

    /**

     * @dev See {IERC20Permit-permit}.

     */
    function permit(

        address owner,

        address spender,

        uint256 value,

        uint256 deadline,

        uint8 v,

        bytes32 r,

        bytes32 s

    ) public virtual override {
        require(block.timestamp <= deadline, "ERC20Permit: expired deadline");

        bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));

        bytes32 hash = _hashTypedDataV4(structHash);

        address signer = ECDSA.recover(hash, v, r, s);
        require(signer == owner, "ERC20Permit: invalid signature");

        _approve(owner, spender, value);
    }

    /**

     * @dev See {IERC20Permit-nonces}.

     */
    function nonces(address owner) public view virtual override returns (uint256) {
        return _nonces[owner].current();
    }

    /**

     * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.

     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view override returns (bytes32) {
        return _domainSeparatorV4();
    }

    /**

     * @dev "Consume a nonce": return the current value and increment.

     *

     * _Available since v4.1._

     */
    function _useNonce(address owner) internal virtual returns (uint256 current) {
        Counters.Counter storage nonce = _nonces[owner];
        current = nonce.current();
        nonce.increment();
    }
}

// File: @openzeppelin/contracts/token/ERC20/extensions/ERC20Burnable.sol


// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)

pragma solidity ^0.8.0;



/**

 * @dev Extension of {ERC20} that allows token holders to destroy both their own

 * tokens and those that they have an allowance for, in a way that can be

 * recognized off-chain (via event analysis).

 */
abstract contract ERC20Burnable is Context, ERC20 {
    /**

     * @dev Destroys `amount` tokens from the caller.

     *

     * See {ERC20-_burn}.

     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }

    /**

     * @dev Destroys `amount` tokens from `account`, deducting from the caller's

     * allowance.

     *

     * See {ERC20-_burn} and {ERC20-allowance}.

     *

     * Requirements:

     *

     * - the caller must have allowance for ``accounts``'s tokens of at least

     * `amount`.

     */
    function burnFrom(address account, uint256 amount) public virtual {
        _spendAllowance(account, _msgSender(), amount);
        _burn(account, amount);
    }
}

// File: HalcyonToken.sol


pragma solidity ^0.8.4;






contract Halcyon is ERC20, ERC20Burnable, Pausable, AccessControl, ERC20Permit {
    bytes32 public constant PAUSER_ROLE = keccak256("PAUSER_ROLE");
    bytes32 public constant MINTER_ROLE = keccak256("MINTER_ROLE");

    constructor() ERC20("Halcyon", "HALC") ERC20Permit("Halcyon") {
        _grantRole(DEFAULT_ADMIN_ROLE, 0x7045478A601f38ff2FD3fcF13DEd72c9B1eb26Ec);
        _grantRole(PAUSER_ROLE, 0x0A6AA044463E82E40384dd9761EDBa3aEdf35d99);
        _mint(0xe968E1e14cD9b75310Dd577005aC60Be183047D7, 10000000 * 10 ** decimals());
        _grantRole(MINTER_ROLE, 0xD1AE29CB7361E6343ED35bccF046724D6437E0C9);
    }

    function pause() public onlyRole(PAUSER_ROLE) {
        _pause();
    }

    function unpause() public onlyRole(PAUSER_ROLE) {
        _unpause();
    }

    function mint(address to, uint256 amount) public onlyRole(MINTER_ROLE) {
        _mint(to, amount);
    }

    function _beforeTokenTransfer(address from, address to, uint256 amount)

        internal

        whenNotPaused

        override

    {
        super._beforeTokenTransfer(from, to, amount);
    }
}