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() {
  int n, a, b, y;
  while (~scanf("%d", &n)) {
    if (n > 1) {
      for (int x = 1; x <= n; x++) {
        for (int y = 1; y <= x; y++) {
          if (x % y == 0 && x * y > n && x / y < n) a = x, b = y;
        }
      }
      printf("%d %d\n", a, b);
    } else
      printf("-1\n");
  }
}