Submission #170234

#	Time	Username	Problem	Language	Result	Execution time	Memory
170234		theboatman	Bomb (IZhO17_bomb)	C++17	24 / 100	47 ms	7392 KiB

bomb

#include <bits/stdc++.h>

#define y1 theboatman
#define make_struct(args...) {args}

using namespace std;
typedef long long ll;

const long long INF = ll(1e18) + 10;
const int inf = int(1e9) + 10;
const int N = int(1e6) + 10;

bool can(int first, int c, int n, int m, vector <string> &a) {
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            if (a[i][j] == '1') {
                int sz = 0;
                while(j < m && a[i][j] == '1') {
                    j++;
                    sz++;
                }
                j--;

                if (sz < c) {
                    return false;
                }
            }
        }
    }

    for(int j = 0; j < m; j++) {
        for(int i = 0; i < n; i++) {
            if (a[i][j] == '1') {
                int sz = 0;
                while(i < n && a[i][j] == '1') {
                    i++;
                    sz++;
                }
                i--;

                if (sz < first) {
                    return false;
                }
            }
        }
    }

    return true;
}

void brute(int n, int m) {
    vector <string> a(n);
    for(int i = 0; i < n; i++) {
        cin >> a[i];
    }

    ll ans = 0;
    for(int first = 1; first <= n; first++) {
        for(int second = 1; second <= m; second++) {
            if (can(first, second, n, m, a)) {
                ans = max(ans, 1LL * first * second);
            }
            else {
                break;
            }
        }
    }

    cout << ans << "\n";
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(0);

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

    if (1LL * n * m * n * m <= int(5e7)) {
        brute(n, m);
        return 0;
    }

    vector <string> a(n);
    for(int i = 0; i < n; i++) {
        cin >> a[i];
    }

    int second = m;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            if (a[i][j] == '1') {
                int sz = 0;
                while(j < m && a[i][j] == '1') {
                    j++;
                    sz++;
                }
                j--;

                second = min(second, sz);
            }
        }
    }

    int first = n;
    for(int j = 0; j < m; j++) {
        for(int i = 0; i < n; i++) {
            if (a[i][j] == '1') {
                int sz = 0;
                while(i < n && a[i][j] == '1') {
                    i++;
                    sz++;
                }
                i--;

                first = min(first, sz);
            }
        }
    }

    cout << 1LL * first * second << "\n";
    return 0;
}
/*
*/

• Subtask 1: 24 / 100