Submission #1248363

#	Time	Username	Problem	Language	Result	Execution time	Memory
1248363		Lithanium	Linear Garden (IOI08_linear_garden)	C++20	100 / 100	74 ms	328 KiB

linear_garden

#include <bits/stdc++.h>
using namespace std;

bitset<1000005> num;
int curr[3][3][2], pre[3][3][2];
int N, M;

int main() {
    cin >> N >> M;
    for (int i = 1; i <= N; i ++) {
        char c;
        cin >> c;
        if (c == 'P') num[i] = 1;
    }
    for (int i = N; i >= 0; i --) {
        memset(curr, 0, sizeof(curr));
        for (int j = 0; j < 3; j ++) {
            for (int k = 0; k < 3; k ++) {
                for (int l = 0; l < 2; l ++) {
                    if (i == N) {
                        curr[j][k][l] = 1;
                        continue;
                    }
                    int top = 1;
                    if (l and num[i+1] == 0) top = 0;
                    // put a 0
                    if (j < 2) curr[j][k][l] = pre[j+1][max(0, k-1)][l and (top == 0)];
                    // put a 1
                    if (top and k < 2) (curr[j][k][l] += pre[max(0, j-1)][k+1][l]) %= M;
                }
            }
        }
        memcpy(pre, curr, sizeof(pre));
    }
    cout << pre[0][0][1];
}

• 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