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;
const long long mod = 1000000007;
void solve() {
  long long n;
  cin >> n;
  for (long long i = 1; i < n + 1; i += 1) {
    for (long long j = 1; j < n + 1; j += 1) {
      if (i % j == 0 && i * j > n && i / j < n) {
        cout << i << ' ' << j << '\n';
        return;
      }
    }
  }
  cout << -1 << '\n';
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  long long tin = 1;
  while (tin--) solve();
  return 0;
}