You have a given integer n. Find the number of ways to fill all 3 × n tiles with the shape described in the picture below. Upon filling, no empty spaces are allowed. Shapes cannot overlap.

<image> This picture describes when n = 4. The left one is the shape and the right one is 3 × n tiles. 

Input

The only line contains one integer n (1 ≤ n ≤ 60) — the length.

Output

Print the number of ways to fill.

Examples

Input


4


Output


4

Input


1


Output


0

Note

In the first example, there are 4 possible cases of filling.

In the second example, you cannot fill the shapes in 3 × 1 tiles.
import io, sys, atexit, os
import math as ma
from sys import exit
from decimal import Decimal as dec
from itertools import permutations


def li ():
	return list (map (int, input ().split ()))


def num ():
	return map (int, input ().split ())


def nu ():
	return int (input ())


def find_gcd ( x, y ):
	while (y):
		x, y = y, x % y
	return x


def lcm ( x, y ):
	gg = find_gcd (x, y)
	return (x * y // gg)


mm = 1000000007
yp = 0


def solve ():
	t = 1
	for _ in range (t):
		n = nu ()
		gp = 3 * n
		if(gp%6!=0):
			print(0)
		else:
			print (pow(2,gp // 6))


if __name__ == "__main__":
	solve ()