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:
x=int(input(""))
flag=0
for i in range(1,x+1):
    if(flag==1):
        break
    for j in range(1,x+1):
        a=i
        b=j
        if(a*b>x and a%b==0 and a/b<x):
            s=str(a)+" "+str(b)
            flag=1
            break

        else:
            continue
if(flag==1):
    print(s)
else:
    print("-1")