<awangdev>254. Factor Combinations_2.java
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;
    }
private List < List < Integer >> var_2 ( int var_3 , int var_4 ) {
  List < List < Integer >> var_6 = new ArrayList < > ( ) ;
  int sqrt = ( int ) Math . sqrt ( var_4 ) ;
  for ( int var_9 = var_3 ;
  var_9 <= sqrt ;
  var_9 ++ ) {
    int var_10 = var_4 / var_9 ;
    if ( var_9 * var_10 == var_4 ) var_6 . add ( Arrays . asList ( var_9 , var_10 ) ) ;
  }
  return var_6 ;
}
