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 supr = 1000000021;
const long double infm = 1e-9;
const long double pipi = acos(-1.0);
long long n, t, jav, k, m, ma;
long long a[100100], b[100100], c[100100];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0), cout.tie(0);
  cin >> n;
  if (n == 1)
    cout << -1;
  else
    cout << n / 2 + 1 << " " << n / 2 + 1;
  return 0;
}