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 ll = long long;
constexpr ll MOD = 1000000007;
using std::cin;
using std::cout;
using std::endl;
using std::list;
using std::map;
using std::multimap;
using std::multiset;
using std::pair;
using std::queue;
using std::set;
using std::sort;
using std::stack;
using std::string;
using std::unordered_map;
using std::unordered_multimap;
using std::unordered_set;
using std::vector;
int main() {
  ll x;
  cin >> x;
  for (ll n = (ll)(1); n < (ll)(x); ++n) {
    for (ll b = (ll)(1); b < (ll)(x + 1); ++b) {
      if (n * b * b > x) {
        cout << n * b << " " << b << endl;
        return 0;
      }
    }
  }
  cout << -1 << endl;
}