在一个3 X N的长方形方格中，铺满1X2的骨牌（骨牌个数不限制），给定N，求方案数.txt

#include<iostream>
using namespace std;
int findnum(int N)
{
	int result;
	if (N % 2 == 0)
		return 0;
	int** dp = new int* [N];
	for (int i = 0; i < N; ++i)
	{
		dp[i] = new int[3];
	}
	for (int i = 0; i < N; ++i)
		for (int j = 0; j < 3; ++j)
			dp[i][j] = 0;
	dp[0][0] = 1;
	dp[0][1] = 0;
	dp[1][0] = 0;
	dp[1][1] = 1;
	dp[1][2] = 0;
	dp[0][2] = 1;
	for (int i = 2; i < N; i++)
	{
		dp[i][0] = dp[i - 2][0] + dp[i - 1][1]+dp[i-2][2];
		dp[i][1] = dp[i - 1][2];
		dp[i][2] = dp[i][0] + dp[i - 1][1];
	}
	result = dp[N-1][0];
	return result;
}
int main()
{
	int N;
	cin >> N;
	cout << findnum(N+1);
	return 0;
}