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:
num = int(input())

a = -1
b = -1

if 1< num <=100:
    '''
    for i in range(1,num+1):
        for j in range(1,num):
            #print ('quem vem primeiro é a '+ str(i)+ ' quem vem por ultimo é b '+ str(j))
            if (i % j) == 0 and (i * j) > num and (j/i) < num and i!=j and i > j:
                a = i
                b = j
                break
               # print (str(a)+ ' ' + str(b) )


    if a != -1 and b != -1: 
        print (str(a)+ ' ' + str(b) )
    else:
        print(-1)'''
    print(str(num) + ' ' + str(num))
else :
    print(-1)