comefrom: <qiyuangong>448_Find_All_Numbers_Disappeared_in_an_Array_1.java
code: public List<Integer> findDisappearedNumbers(int[] nums) {
          List<Integer> ret = new ArrayList<Integer>();
          
          for(int i = 0; i < nums.length; i++) {
              int val = Math.abs(nums[i]) - 1;
              if(nums[val] > 0) {
                  nums[val] = -nums[val];
              }
          }
          
          for(int i = 0; i < nums.length; i++) {
              if(nums[i] > 0) {
                  ret.add(i+1);
              }
          }
          return ret;
      }
masked: public List < Integer > var_1 ( int [ ] var_2 ) {
    List < Integer > var_5 = new ArrayList < Integer > ( ) ;
    for ( int var_7 = 0 ;
    var_7 < var_2 . length ;
    var_7 ++ ) {
      int var_12 = Math . abs ( var_2 [ var_7 ] ) - 1 ;
      if ( var_2 [ var_12 ] > 0 ) {
        var_2 [ var_12 ] = - var_2 [ var_12 ] ;
      }
    }
    for ( int var_7 = 0 ;
    var_7 < var_2 . length ;
    var_7 ++ ) {
      if ( var_2 [ var_7 ] > 0 ) {
        var_5 . add ( var_7 + 1 ) ;
      }
    }
    return var_5 ;
  }
  