comefrom: <awangdev>136. Single Number_1.java
code: public int singleNumber(int[] nums) {
          if (nums == null || nums.length == 0) return 0;
          int result = 0;
          for (int i : nums) {
              result = result ^ i;
          }
          return result;
      }
masked: public int sample_funcname ( int [ ] var_0 ) {
    if ( var_0 == null || var_0 . length == 0 ) return 0 ;
    int var_4 = 0 ;
    for ( int var_5 : var_0 ) {
      var_4 = var_4 ^ var_5 ;
    }
    return var_4 ;
  }
  