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>
int main() {
  unsigned short k, max, x;
  std::cin >> x;
  if (x == 2 || x == 3) {
    std::cout << 2 << " " << 2;
    return 0;
  }
  unsigned short b = (unsigned short)sqrt(x);
  while (b >= 1) {
    k = x / (b * b);
    max = x / b;
    while (k <= max) {
      if (k * b * b > x && k * b <= x) {
        std::cout << k * b << " " << b;
        return 0;
      }
      ++k;
    }
    --b;
  }
  std::cout << -1;
  return 0;
}