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:
# region input types declaration

INT_VALUE = "INT_VALUE"
INT_ARRAY = "INT_ARRAY"
STRING = "STRING"
STRING_ARRAY = "STRING_ARRAY"
LINES_ARRAY = "LINES_ARRAY"

# endregion

# region input types acquiring


def get_int_value(content):
    return int(content)


def get_int_array(content):
    return [int(x) for x in filter(None, content.split(' '))]


def get_string(content):
    return content


def get_string_array(content):
    return content.split(' ')


def get_lines_array(content):
    return content.split('\n')

# endregion

# region input types dictionary


GET_INPUT = {
    INT_VALUE: get_int_value,
    INT_ARRAY: get_int_array,
    STRING: get_string,
    STRING_ARRAY: get_string_array,
    LINES_ARRAY: get_lines_array
}

# endregion

INPUT_TYPE = INT_VALUE

# region stuff


def process(solver):
    content = GET_INPUT[INPUT_TYPE](input())
    result = solver(content)
    print(str(result))


#endregion


def solve(_input):
    return "-1" if _input == 1 else str(_input - _input%2) + " 2"


process(solve)