comefrom: <awangdev>347. Top K Frequent Elements_1.java
code: private Map<Integer, Integer> buildFreqMap(int[] nums) { 
          Map<Integer, Integer> map = new HashMap<>();
          for (int num : nums) map.put(num, map.getOrDefault(num, 0) + 1);
          return map;
      }
masked: private Map < Integer , Integer > var_0 ( int [ ] var_1 ) {
    Map < Integer , Integer > var_2 = new HashMap < > ( ) ;
    for ( int var_3 : var_1 ) var_2 . put ( var_3 , var_2 . getOrDefault ( var_3 , 0 ) + 1 ) ;
    return var_2 ;
  }
  