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())
arr=[]
if x==2:
    print(2,2)
elif x==3:
    print(3,3)
else:
    for i in range(1,x+1,1):
        arr.append(i)
    temp=0
    for i in range(0,len(arr)-1,1):
        b=arr[i]
        temp=0
        for j in range(i+1,len(arr),1):
            a=arr[j]
            if a%b==0:
                if a*b > x:
                    if a//b<x:
                        print(a,b)
                        temp=1
                        break
        if temp==1:
            break
    if temp!=1:
        print(-1)