Submission #1233436

#	Time	Username	Problem	Language	Result	Execution time	Memory
1233436		antonn	Soccer Stadium (IOI23_soccer)	C++20	0 / 100	8 ms	15684 KiB

soccer

#include "soccer.h"
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N = 1000 + 7;
const int M = 30 + 7;

int a[N][N], pref[N][N];
int dp[M][M][M][M];

/*
5
0 0 0 0 0
1 0 0 0 0
0 0 0 0 0
0 0 0 0 0
0 0 1 0 0 
*/

bool ok(int l, int x, int y) {
    return pref[l][y] - pref[l][x - 1] == 0;
}

int biggest_stadium(int n, vector<vector<int>> f) {
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= n; ++j) {
            a[i][j] = f[i - 1][j - 1];
            pref[i][j] = pref[i][j - 1] + a[i][j];
        }
    }
    
    {
        vector<pair<int, int>> p(n + 1);
        bool all = 1;
        int total = 0;
        for (int i = 1; i <= n; ++i) {
            int cnt = 0;
            int l = 1e9, r = 0;
            for (int j = 1; j <= n; ++j) {
                if (a[i][j] == 0) {
                    ++cnt;
                    l = min(l, j);
                    r = max(r, j);
                }
            }
            p[i] = {l, r};
            if (cnt != 0 && r - l + 1 != cnt) {
                all = 0;
            } 
            total += cnt;
        }
        int lines = 0;
        for (int i = 1; i <= n; ++i) if (p[i].first != 1e9) lines++;
        int f = -1, l = -1;
        for (int i = 1; i <= n; ++i) {
            if (p[i].first != 1e9) {
                if (f == -1) f = i;
                l = i;
            }
        }
        if (l - f + 1 != lines) all = false;
        for (int i = f; i <= l; ++i) {
            for (int j = i; j <= l; ++j) {
                if (p[i].first <= p[j].first && p[j].second <= p[i].second) continue;
                if (p[j].first <= p[i].first && p[i].second <= p[j].second) continue;
                all = 0;
            }
        }
        if (all) return total;
        if (n > 30) return -1;
    }
    
    
    for (int down = 0; down < N; ++down) {
        for (int up = down; up < N; ++up) {
            for (int x = 0; x < N; ++x) {
                for (int y = x; y < N; ++y) {
                    dp[down][up][x][y] = -1e9;
                }
            }
        }
    }
    for (int i = 1; i <= n; ++i) {
        for (int l = 1; l <= n; ++l) {
            for (int r = l; r <= n; ++r) {
                if (ok(i, l, r)) dp[i][i][l][r] = r - l + 1;
            }
        }
    }
    for (int h = n; h >= 1; --h) {
        for (int l = 1; l + h - 1 <= n; ++l) {
            int r = l + h - 1;
            for (int h2 = 1; h2 <= n; ++h2) {
                for (int down = 1; down + h2 - 1 <= n; ++down) {
                    int up = down + h2 - 1;
                    for (int x = l; x <= r; ++x) {
                        for (int y = x; y <= r; ++y) {
                            if (ok(down - 1, x, y)) {
                                dp[down - 1][up][x][y] = max(dp[down - 1][up][x][y], dp[down][up][l][r] + y - x + 1);
                            }
                            if (ok(up + 1, x, y)) {
                                dp[down][up + 1][x][y] = max(dp[down][up + 1][x][y], dp[down][up][l][r] + y - x + 1);
                            }
                        }
                    }
                }
            }
        }
    }
    int ans = 0;
    for (int down = 1; down <= n; ++down) {
        for (int up = down; up <= n; ++up) {
            for (int l = 1; l <= n; ++l) {
                for (int r = l; r <= n; ++r) {
                    ans = max(ans, dp[down][up][l][r]);
                }
            }
        }
    }
    return ans;
}

• 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