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;
  cin >> n;
  if (n == 2 || n == 3) {
    cout << 2 << " " << 2;
    return 0;
  }
  if (n <= 1) {
    cout << -1;
    return 0;
  }
  long long root = sqrt(n);
  long long temp = root * root;
  long long i = 0;
  while (1) {
    if (temp * i > n) {
      cout << (temp * i) / root << " " << root;
      break;
    }
    i++;
  }
  return 0;
}