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:

try :
    x = int(input()) 
    a=b=-1
    flag=0
    for each_a in range (1,x+1,1): 
        if(flag==0):
            for each_b in range (1, each_a+1):
                if( each_a%each_b == 0): 
                    if(each_b*each_a > x) : 
                        if(a/b < x and flag==0):
                            flag=1
                            print(each_a,each_b) 
                            break
            
            
    if(flag==0):
        print(flag-1)
    
except :
    pass