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 x, i, j, a = 0, b = 0;
  scanf("%d", &x);
  for (i = 1; i <= x; i++) {
    for (j = 1; j <= x; j++) {
      if ((i * j) > x && (i / j) < x && i % j == 0) {
        a = i;
        b = j;
        break;
      }
    }
  }
  if (a == 0 && b == 0)
    printf("-1\n");
  else
    printf("%d %d\n", a, b);
  return 0;
}