Problem: Given an integer x, find 2 integers a and b such that: 

  * 1 ≤ a,b ≤ x 
  * b divides a (a is divisible by b). 
  * a ⋅ b>x. 
  * a/b<x. 

Input

The only line contains the integer x (1 ≤ x ≤ 100).

Output

You should output two integers a and b, satisfying the given conditions, separated by a space. If no pair of integers satisfy the conditions above, print "-1" (without quotes).

Examples

Input

10


Output

6 3

Input

1


Output

-1

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
int main() {
  int x;
  ;
  ;
  cin >> x;
  if (x == 1) {
    cout << -1;
    return 0;
  }
  if (x == 3) {
    cout << "3 3";
    return 0;
  }
  int val = ceil(x / 2.0);
  if (val % 2 == 0) {
    cout << val + 2 << ' ' << 2;
  } else {
    cout << val + 1 << ' ' << 2;
    ;
    ;
    ;
    ;
    ;
    ;
  }
}