Submission #557483

#	Time	Username	Problem	Language	Result	Execution time	Memory
557483		alextodoran	Dango Maker (JOI18_dango_maker)	C++17	100 / 100	282 ms	35680 KiB

dango_maker

/**
 ____ ____ ____ ____ ____
||a |||t |||o |||d |||o ||
||__|||__|||__|||__|||__||
|/__\|/__\|/__\|/__\|/__\|

**/

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int D_MAX = 3000;

int N, M;
char mat[D_MAX + 2][D_MAX + 2];

bool H[D_MAX + 2][D_MAX + 2];
bool V[D_MAX + 2][D_MAX + 2];

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    cin >> N >> M;
    for (int i = 1; i <= N; i++) {
        for (int j = 1; j <= M; j++) {
            cin >> mat[i][j];
        }
    }

    for (int i = 1; i <= N; i++) {
        for (int j = 1; j <= M; j++) {
            if (mat[i][j] == 'G') {
                if (1 < j && j < M && mat[i][j - 1] == 'R' && mat[i][j + 1] == 'W') {
                    H[i][j] = true;
                }
                if (1 < i && i < N && mat[i - 1][j] == 'R' && mat[i + 1][j] == 'W') {
                    V[i][j] = true;
                }
            }
        }
    }

    int answer = 0;
    for (int s = 1 + 1; s <= N + M; s++) {
        int i1 = max(1, s - M), i2 = min(N, s - 1);
        int dp[2][3];
        dp[0][0] = dp[0][1] = dp[0][2] = 0;
        for (int i = i1; i <= i2; i++) {
            int j = s - i;
            dp[1][0] = max({dp[0][0], dp[0][1], dp[0][2]});
            if (H[i][j] == true) {
                dp[1][1] = max(dp[0][0], dp[0][1]) + 1;
            } else {
                dp[1][1] = 0;
            }
            if (V[i][j] == true) {
                dp[1][2] = max(dp[0][0], dp[0][2]) + 1;
            } else {
                dp[1][2] = 0;
            }
            swap(dp[0], dp[1]);
        }
        answer += max({dp[0][0], dp[0][1], dp[0][2]});
    }
    cout << answer << "\n";

    return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 20 / 20
• Subtask 3: 67 / 67