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 argc, const char* argv[]) {
  int n;
  cin >> n;
  if (n == 1) {
    cout << -1;
    return 0;
  } else {
    for (int i = n; i > 1; --i) {
      for (int j = 2; j <= n; j++) {
        if (i * j > n && i % j == 0) {
          cout << i << " " << j;
          return 0;
        }
      }
    }
  }
  cout << -1;
  return 0;
}