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 PYTHON3):

Solution:
from collections import deque
from math import ceil,floor,sqrt,gcd
def ii(): return int(input())
def mi(): return map(int,input().split())
def li(): return list(mi())
def si():return input()
def fun(x):
    for i in range(1,x+1):
        a=i
        for j in range(1,i+1):
            b=j
            if(a%b==0):
                y=a//b
                if(a*b>x and y<x):
                    print(a,b)
                    return
    print('-1')
    return
x=ii()
fun(x)