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;
long long modulo(long long base, long long exp, long long m);
int main() {
  int x;
  cin >> x;
  if (x <= 1)
    cout << "-1";
  else {
    cout << x << " " << x;
  }
  return 0;
}
long long modulo(long long base, long long exp, long long m) {
  long long answer = 1;
  while (exp > 0) {
    if (exp % 2 == 1) answer = (answer * base) % m;
    exp = exp / 2;
    base = (base * base) % m;
  }
  return answer;
}