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 PYTHON):

Solution:
import math 
  
# A function to print all prime factors of  
# a given number n 
def primeFactors(n): 
    l=[]
    # Print the number of two's that divide n 
    while n % 2 == 0: 
        l.append(2) 
        n = n / 2
          
    # n must be odd at this point 
    # so a skip of 2 ( i = i + 2) can be used 
    for i in range(3,int(math.sqrt(n))+1,2): 
          
        # while i divides n , print i ad divide n 
        while n % i== 0: 
            l.append(i) 
            n = n / i 
              
    # Condition if n is a prime 
    # number greater than 2 
    if n > 2: 
        l.append(n)
    return l

          
x=input()
l=primeFactors(x)
if x<2:
    print -1
elif x==2:
    print 2,2
else:
    if len(l)==1:
        print x-1,2
    else:
        print x,l[0]