Submission #396589

#	Time	Username	Problem	Language	Result	Execution time	Memory
396589		Berted	Linear Garden (IOI08_linear_garden)	C++14	100 / 100	124 ms	2396 KiB

linear_garden

#include <iostream>
using namespace std;

int N, M, DP[2][3][3][2];
string S;

int main()
{
	ios :: sync_with_stdio(0); cin.tie(0);
	cin >> N >> M >> S;
	DP[0][0][0][1] = 1;
	for (int i = 0; i < N; i++)
	{
		for (int j = 0; j < 3; j++)
			for (int k = 0; k < 3; k++)
				DP[~i & 1][j][k][0] = DP[~i & 1][j][k][1] = 0;

		for (int j = 0; j < 3; j++)
		{
			for (int k = 0; k < 3; k++)
			{
				if (j + 1 < 3) 
				{
					DP[~i & 1][j + 1][max(0, k - 1)][0] = (DP[~i & 1][j + 1][max(0, k - 1)][0] + DP[i & 1][j][k][0]) % M;
					if (S[i] == 'L') DP[~i & 1][j + 1][max(0, k - 1)][1] = (DP[~i & 1][j + 1][max(0, k - 1)][1] + DP[i & 1][j][k][1]) % M;
					else DP[~i & 1][j + 1][max(0, k - 1)][0] = (DP[~i & 1][j + 1][max(0, k - 1)][0] + DP[i & 1][j][k][1]) % M;
				}
				if (k + 1 < 3) 
				{
					DP[~i & 1][max(0, j - 1)][k + 1][0] = (DP[~i & 1][max(0, j - 1)][k + 1][0] + DP[i & 1][j][k][0]) % M;
					if (S[i] == 'P') DP[~i & 1][max(0, j - 1)][k + 1][1] = (DP[~i & 1][max(0, j - 1)][k + 1][1] + DP[i & 1][j][k][1]) % M;
				}
			}
		}
	}
	int ret = 0;
	for (int j = 0; j < 3; j++)
	{
		for (int k = 0; k < 3; k++) ret = (ret + DP[N & 1][j][k][0]) % M;
	}
	cout << (ret + 1) % M << "\n";
	return 0;
}

• Subtask 1: 2 / 2
• Subtask 2: 2 / 2
• Subtask 3: 4 / 4
• Subtask 4: 4 / 4
• Subtask 5: 4 / 4
• Subtask 6: 4 / 4
• Subtask 7: 4 / 4
• Subtask 8: 4 / 4
• Subtask 9: 4 / 4
• Subtask 10: 4 / 4
• Subtask 11: 4 / 4
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5
• Subtask 21: 5 / 5
• Subtask 22: 5 / 5
• Subtask 23: 5 / 5