Filling Shapes

题意翻译

输入$n$,求用三个方块组成的可旋转、翻转的“L”型砖块铺满$3 \times n$的网格的方案数。

题目描述

You have a given integer $ n $ . Find the number of ways to fill all $ 3 \times n $ tiles with the shape described in the picture below. Upon filling, no empty spaces are allowed. Shapes cannot overlap.  This picture describes when $ n = 4 $ . The left one is the shape and the right one is $ 3 \times n $ tiles.

输入输出格式

输入格式

The only line contains one integer $ n $ ( $ 1 \le n \le 60 $ ) — the length.

输出格式

Print the number of ways to fill.

输入输出样例

输入样例 #1

4

输出样例 #1

4

输入样例 #2

1

输出样例 #2

0

说明

In the first example, there are $ 4 $ possible cases of filling. In the second example, you cannot fill the shapes in $ 3 \times 1 $ tiles.

题意翻译

输入$n$,求用三个方块组成的可旋转、翻转的“L”型砖块铺满$3 \times n$的网格的方案数。