Submission #1067764

#	Time	Username	Problem	Language	Result	Execution time	Memory
1067764		becaido	Soccer Stadium (IOI23_soccer)	C++17	77.50 / 100	518 ms	753492 KiB

soccer

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,popcnt,sse4,abm")
#include <bits/stdc++.h>
using namespace std;

#ifndef WAIMAI
#include "soccer.h"
#else
#include "grader.cpp"
#endif

#ifdef WAIMAI
#define debug(HEHE...) cout << "[" << #HEHE << "] : ", dout(HEHE)
void dout() {cout << '\n';}
template<typename T, typename...U>
void dout(T t, U...u) {cout << t << (sizeof...(u) ? ", " : ""), dout(u...);}
#else
#define debug(...) 7122
#endif

#define ll long long
#define Waimai ios::sync_with_stdio(false), cin.tie(0)
#define FOR(x,a,b) for (int x = a, I = b; x <= I; x++)
#define pb emplace_back
#define F first
#define S second

const int SIZE = 505;

int n, ans;
bool a[SIZE << 2][SIZE << 2];
int L[SIZE][SIZE][SIZE], R[SIZE][SIZE][SIZE], dp[SIZE][SIZE][SIZE];

int big() {
    int cnt = 0, x = 0, y = 0;
    FOR (i, 1, n) FOR (j, 1, n) if (a[i][j]) {
        cnt++;
        x = i, y = j;
    }
    if (cnt == 0) return n * n;
    if (cnt == 1) return n * n - min(x, n - x + 1) * min(y, n - y + 1);
    {
        vector<pair<int, int>> seg;
        FOR (i, 1, n) {
            vector<pair<int, int>> v;
            int l = 0;
            FOR (j, 1, n) if (a[i][j] == 0) {
                if (l == 0) l = j;
                if (j == n || a[i][j + 1]) {
                    v.pb(l, j);
                    l = 0;
                }
            }
            if (v.size() > 1) return 0;
            seg.insert(seg.end(), v.begin(), v.end());
        }
        sort(seg.begin(), seg.end(), [&](auto x, auto y) {
            return x.F != y.F ? x.F < y.F : x.S > y.S;
        });
        FOR (i, 1, seg.size() - 1) {
            auto [pl, pr] = seg[i - 1];
            auto [l, r] = seg[i];
            if (l < pl || r > pr) return 0;
        }
    }
    {
        vector<pair<int, int>> seg;
        FOR (i, 1, n) {
            vector<pair<int, int>> v;
            int l = 0;
            FOR (j, 1, n) if (a[j][i] == 0) {
                if (l == 0) l = j;
                if (j == n || a[j + 1][i]) {
                    v.pb(l, j);
                    l = 0;
                }
            }
            if (v.size() > 1) return 0;
            seg.insert(seg.end(), v.begin(), v.end());
        }
        sort(seg.begin(), seg.end(), [&](auto x, auto y) {
            return x.F != y.F ? x.F < y.F : x.S > y.S;
        });
        FOR (i, 1, seg.size() - 1) {
            auto [pl, pr] = seg[i - 1];
            auto [l, r] = seg[i];
            if (l < pl || r > pr) return 0;
        }
    }
    return n * n - cnt;
}

int biggest_stadium(int N, vector<vector<int>> F) {
    n = N;
    FOR (i, 1, n) FOR (j, 1, n) a[i][j] = F[i - 1][j - 1];
    if (n > 500) return big();
    FOR (i, 1, n) {
        FOR (j, 1, n) if (a[i][j] == 0) L[i][i][j] = (j > 1 && a[i][j - 1] == 0 ? L[i][i][j - 1] : j);
        for (int j = n; j >= 1; j--) if (a[i][j] == 0) R[i][i][j] = (j < n && a[i][j + 1] == 0 ? R[i][i][j + 1] : j);
    }
    FOR (u, 1, n) FOR (d, u + 1, n) FOR (j, 1, n) {
        if (L[u][d - 1][j] && L[d][d][j]) L[u][d][j] = max(L[u][d - 1][j], L[d][d][j]);
        if (R[u][d - 1][j] && R[d][d][j]) R[u][d][j] = min(R[u][d - 1][j], R[d][d][j]);
    }
    FOR (i, 1, n) FOR (j, 1, n) if (L[i][i][j]) dp[i][i][j] = R[i][i][j] - L[i][i][j] + 1, ans = max(ans, dp[i][i][j]);
    FOR (d, 1, n) for (int u = d - 1; u >= 1; u--) FOR (j, 1, n) if (L[u][d][j]) {
        dp[u][d][j] = max(dp[u][d - 1][j], dp[u + 1][d][j]) + R[u][d][j] - L[u][d][j] + 1;
        ans = max(ans, dp[u][d][j]);
    }
    return ans;
}

/*
in1
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
out1
20
*/

• Subtask 0: 0 / 0
• Subtask 1: 6 / 6
• Subtask 2: 8 / 8
• Subtask 3: 22 / 22
• Subtask 4: 18 / 18
• Subtask 5: 16 / 16
• Subtask 6: 7.5 / 30