Submission #677787

#	Time	Username	Problem	Language	Result	Execution time	Memory
677787		bashkort	Furniture (JOI20_furniture)	C++17	0 / 100	10 ms	1620 KiB

furniture

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

constexpr int N = 1004, dx[]{0, 0, -1, 1}, dy[]{-1, 1, 0, 0};

int c[N][N], dead[N][N], cnt[2 * N];

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m;
    cin >> n >> m;

    queue<pair<int, int>> consider;

    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j) {
            cin >> c[i][j];

            if (c[i][j]) {
                consider.emplace(i, j);
            }

            cnt[i + j] += 1;
        }
    }
    for (int j = 2; j <= m + 1; ++j) {
        c[0][j] = 1;
        consider.emplace(0, j);
    }
    for (int i = 2; i <= n + 1; ++i) {
        c[i][0] = 1;
        consider.emplace(i, 0);
    }
    for (int j = 0; j <= m - 1; ++j) {
        c[n + 1][j] = 1;
        consider.emplace(n + 1, j);
    }
    for (int i = 0; i <= n - 1; ++i) {
        c[i][m + 1] = 1;
        consider.emplace(i, m + 1);
    }


    auto normalize = [&]() {
        while (!consider.empty()) {
            auto [i, j] = consider.front();
            consider.pop();

            if (c[i][j] || i && j && dead[i - 1][j] && dead[i][j - 1] || dead[i][j + 1] && dead[i + 1][j]) {
                dead[i][j] = 1;
            }

            if (dead[i][j]) {
                for (int k = 0; k < size(dx); ++k) {
                    int ni = i + dx[k], nj = j + dy[k];
                    if (ni > 0 && nj > 0 && ni < n + 1 && nj < m + 1 && !dead[ni][nj]) {
                        consider.emplace(ni, nj);
                    }
                }
                if (i && i <= n && j && j <= m) {
                    cnt[i + j] -= 1;
                }
            }
        }
    };

    normalize();

    int q;
    cin >> q;

    while (q--) {
        int i, j;
        cin >> i >> j;

        if (dead[i][j]) {
            c[i][j] = 1;
            cout << "1\n";
            continue;
        }

        if (cnt[i + j] > 1) {
            c[i][j] = 1;

            consider.emplace(i, j);
            normalize();

            cout << "1\n";
        } else {
            cout << "0\n";
        }
    }

    return 0;
}

Compilation message (stderr)

furniture.cpp: In lambda function:
furniture.cpp:53:53: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   53 |             if (c[i][j] || i && j && dead[i - 1][j] && dead[i][j - 1] || dead[i][j + 1] && dead[i + 1][j]) {
      |                            ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
furniture.cpp:53:89: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   53 |             if (c[i][j] || i && j && dead[i - 1][j] && dead[i][j - 1] || dead[i][j + 1] && dead[i + 1][j]) {
      |                                                                          ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
furniture.cpp:58:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::size_t' {aka 'long unsigned int'} [-Wsign-compare]
   58 |                 for (int k = 0; k < size(dx); ++k) {
      |                                 ~~^~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 95