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() {
  long long n;
  ios_base::sync_with_stdio(0);
  cin >> n;
  long long i, j;
  for (i = 1; i <= n; i++) {
    for (j = 1; j < n; j++) {
      if (i * j * i <= n) continue;
      break;
    }
    if (j < n) break;
  }
  if (i > n)
    cout << -1 << '\n';
  else
    cout << i * j << ' ' << i << '\n';
  return 0;
}