Submission #994147

#	Time	Username	Problem	Language	Result	Execution time	Memory
994147		stdfloat	Soccer Stadium (IOI23_soccer)	C++17	0 / 100	4550 ms	3420 KiB

soccer

#include <bits/stdc++.h>
#include "soccer.h"
using namespace std;
 
int n, mx;
 
vector<int> dx = {-1, 0, 1, 0}, dy = {0, 1, 0, -1};

vector<vector<int>> a, v;
 
void f(int x) {
    if (x == n * n) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                if (!v[i][j]) continue;

                vector<vector<bool>> vis(n, vector<bool>(n));
                vis[i][j] = true;
                for (int z = 0; z < 2; z++) {
                    vector<vector<bool>> vis2(n, vector<bool>(n));
                    for (int k = 0; k < n; k++) {
                        for (int l = 0; l < n; l++) {
                            if (!vis[k][l]) continue;
 
                            for (int m = l - 1; m >= 0 && v[k][m]; m--)
                                vis2[k][m] = true;
                            for (int m = l + 1; m < n && v[k][m]; m++)
                                vis2[k][m] = true;
 
                            for (int m = k - 1; m >= 0 && v[m][l]; m--)
                                vis2[m][l] = true;
                            for (int m = k + 1; m < n && v[m][l]; m++)
                                vis2[m][l] = true;
                        }
                    }

                    for (int k = 0; k < n; k++) {
                        for (int l = 0; l < n; l++)
                            if (vis2[k][l]) vis[k][l] = true;
                    }
                }
 
                for (int k = 0; k < n; k++) {
                    for (int l = 0; l < n; l++)
                        if (v[k][l] && !vis[k][l]) return;
                }
            }
        }
 
        int cnt = 0;
        for (auto i : v)
            cnt += count(i.begin(), i.end(), 1);

        mx = max(mx, cnt);
 
        return;
    }
 
    for (int i = 0; i < 2; i++) {
        if (i && a[x / n][x % n]) return;

        v[x / n][x % n] = i;
        f(x + 1);
    }
}

int biggest_stadium(int N, vector<vector<int>> F) {
    n = N; a = F;
 
    int cnt = 0;
    for (auto i : a)
        cnt += count(i.begin(), i.end(), 1);

    bool tr = true;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (a[i][j]) continue;
 
            vector<vector<bool>> vis(n, vector<bool>(n));
            vis[i][j] = true;
            for (int z = 0; z < 2; z++) {
                vector<vector<bool>> vis2(n, vector<bool>(n));
                for (int k = 0; k < n; k++) {
                    for (int l = 0; l < n; l++) {
                        if (!vis[k][l]) continue;
 
                        for (int m = l - 1; m >= 0 && !a[k][m]; m--)
                            vis2[k][m] = true;
                        for (int m = l + 1; m < n && !a[k][m]; m++)
                            vis2[k][m] = true;
 
                        for (int m = k - 1; m >= 0 && !a[m][l]; m--)
                            vis2[m][l] = true;
                        for (int m = k + 1; m < n && !a[m][l]; m++)
                            vis2[m][l] = true;
                    }
                }
 
                for (int k = 0; k < n; k++) {
                    for (int l = 0; l < n; l++)
                        if (vis2[k][l]) vis[k][l] = true;
                }
            }
 
            for (int k = 0; k < n; k++) {
                for (int l = 0; l < n; l++)
                    if (!a[k][l] && !vis[k][l]) tr = false;
            }
        }
    }

    vector<vector<bool>> vis(n, vector<bool>(n));
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (!a[i][j]) {
                queue<pair<int, int>> q;
                q.push({i, j});
                while (!q.empty()) {
                    auto [x, y] = q.front(); q.pop();
                    vis[x][y] = true;

                    for (int i = 0; i < 4; i++) {
                        int nx = x + dx[i], ny = y + dy[i];
                        if (0 <= min(nx, ny) && max(nx, ny) < n && !a[nx][ny] && !vis[nx][ny]) {
                            vis[nx][ny] = true;
                            q.push({nx, ny});
                        }
                    }
                }

                break;
            }
        }
    }

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++)
            if (!a[i][j] && !vis[i][j]) return 0;
    }
 
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++)
            if (a[i][j] && 2 < ((i && !a[i - 1][j]) + (i + 1 < n && !a[i + 1][j]) + (j && !a[i][j - 1]) + (j + 1 < n && !a[i][j + 1]))) return 0;
    }

    assert(tr);

    return n * n - cnt;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 6
• Subtask 2: 0 / 8
• Subtask 3: 0 / 22
• Subtask 4: 0 / 18
• Subtask 5: 0 / 16
• Subtask 6: 0 / 30