comefrom: <awangdev>254. Factor Combinations_2.java
code: private List<List<Integer>> calcFactors(int lastFactor, int num) {
  
          List<List<Integer>> rst = new ArrayList<>();
          int sqrt = (int)Math.sqrt(num);
          for (int i = lastFactor; i <= sqrt; i++) { 
              int remain = num / i;
              if (i * remain == num) rst.add(Arrays.asList(i, remain));
          }
          return rst;
      }
masked: private List < List < Integer >> var_0 ( int var_1 , int var_2 ) {
    List < List < Integer >> var_3 = new ArrayList < > ( ) ;
    int sqrt = ( int ) Math . sqrt ( var_2 ) ;
    for ( int var_4 = var_1 ;
    var_4 <= sqrt ;
    var_4 ++ ) {
      int var_5 = var_2 / var_4 ;
      if ( var_4 * var_5 == var_2 ) var_3 . add ( Arrays . asList ( var_4 , var_5 ) ) ;
    }
    return var_3 ;
  }
  