题目描述
In how many ways can you tile a 3xn rectangle with 2×1 dominoes?
Here is a sample tiling of a 3×12 rectangle.
Input consists of several test cases followed by a line containing -1. Each test case is a line containing an integer 0 ≤ n ≤ 30. For each test case, output one integer number giving the number of possible tilings.
输入
暂无
输出
暂无
样例输入
2
8
12
-1
样例输出
3
153
2131
参考代码
#include<stdio.h>
int main()
{
int n,i,a[31];
a[0]=1;
a[2]=3;
a[4]=11;
for (i=6;i<31;i+=2)
a[i]=a[i-2]*4-a[i-4];
while(scanf("%d",&n)!=EOF,n!=-1)
{
if(n%2==0)
printf("%dn",a[n]);
else
printf("0n");
}
return 0;
}
解析
暂无
