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() {
  int a, b, c, x, i = 0;
  cin >> x;
  if (x > 100 || x < 1) {
    std::cout << "-1" << std::endl;
    exit(0);
  }
  for (b = 1; b <= x; b++) {
    for (c = 1; c < x; c++) {
      a = c * b;
      if (a * b > x && a <= x) {
        cout << a << " " << b << endl;
        i++;
      }
      if (i == 1) break;
    }
    if (i == 1) break;
  }
  if (i == 0) std::cout << "-1" << std::endl;
}