comefrom: <awangdev>105. Construct Binary Tree from Preorder and Inorder Traversal_1.java
code: private Map<Integer, Integer> buildMap(int[] inorder) {
  
          Map<Integer, Integer> map = new HashMap<>();
          for (int i = 0; i < inorder.length; i++) map.put(inorder[i], i);
          return map;
      }
masked: private Map < Integer , Integer > var_1 ( int [ ] var_2 ) {
    Map < Integer , Integer > var_5 = new HashMap < > ( ) ;
    for ( int var_7 = 0 ;
    var_7 < var_2 . length ;
    var_7 ++ ) var_5 . put ( var_2 [ var_7 ] , var_7 ) ;
    return var_5 ;
  }
  