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 int power(long long int x, unsigned long long int y,
                    long long int p) {
  long long int res = 1;
  x = x % p;
  while (y > 0) {
    if (y & 1) res = (res * x) % p;
    y = y >> 1;
    x = (x * x) % p;
  }
  return res;
}
long long int n, m, k;
int32_t main() {
  long long int x;
  cin >> x;
  if (x == 1) {
    cout << -1;
    return 0;
  }
  if (x == 2) {
    cout << 2 << " " << 2;
    return 0;
  }
  if (x % 2 == 0) {
    cout << x << " " << 2 << endl;
  } else {
    cout << (x - 1) << " " << 2 << endl;
  }
}