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 gcd(long long a, long long b) { return b == 0 ? a : gcd(b, a % b); }
const int N = 2e3 + 100;
vector<long long> v;
int q, n, x, m;
string second;
map<int, int> mp;
int main() {
  cin >> x;
  for (int i = 1; i <= x; ++i) {
    for (int j = 1; j <= x; ++j) {
      if (i <= x && j <= x) {
        if (i % j == 0) {
          if (i * j > x) {
            if (i / j < x) {
              cout << i << " " << j;
              return 0;
            }
          }
        }
      }
    }
  }
  cout << -1;
}