Submission #220726

#	Time	Username	Problem	Language	Result	Execution time	Memory
220726		NONAME	Skandi (COCI20_skandi)	C++17	55 / 110	3940 ms	18040 KiB

Main

#include <bits/stdc++.h>
#include <time.h>
//#include <random>
//#ifndef _LOCAL
//#pragma GCC optimize("-O3")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#endif
#define sz(x) int(x.size())
#define in(x) freopen(x, "r", stdin)
#define out(x) freopen(x, "w", stdout)
#define N 100500
#define oo ll(1e16)
#define pii pair <int, int>
#define pll pair <ll, ll>
#define ft first
#define sd second
#define pb push_back
#define ppb pop_back
#define mp make_pair
#define el '\n'
#define elf endl
#define base ll(1e9 + 7)
#define re return
#define nins 4294967295
using namespace std;
typedef long long ll;
typedef long double ld;

//mt19937 rnd(0);

pii ver_co[501 * 501], hor_co[501 * 501];
int n, m, ver, hor;
vector <int> mV, mH, g[501 * 501], mt;
vector <char> mk;
map <pii, int> ver_id, hor_id;
string s[501];

bool try_kuhn(int v) {
    if (mk[v])
        return 0;
    mk[v] = 1;

    for (int i = 0; i < sz(g[v]); i++) {
        int to = g[v][i];

        if (mt[to] == -1 || try_kuhn(mt[to])) {
            mt[to] = v;
            return 1;
        }
    }

    return 0;
}

void solve() {
    cin >> n >> m;
    for (int i = 0; i < n; i++)
        cin >> s[i];

    for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++) {
        if (s[i][j] == '0')
            continue;

        if (i + 1 < n && s[i + 1][j] == '0') {
            ver_id[{i, j}] = ver;
            ver_co[ver++] = {i + 1, j + 1};
        }

        if (j + 1 < m && s[i][j + 1] == '0') {
            hor_id[{i, j}] = hor;
            hor_co[hor++] = {i + 1, j + 1};
        }
    }

    for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++) {
        if (s[i][j] == '1')
            continue;

        int _i = i, _j = j;

        while (s[_i][j] == '0') _i--;

        while (s[i][_j] == '0') _j--;

        g[ver_id[{_i, j}]].pb(hor_id[{i, _j}]);
    }

    int rs = 0;
    mt.assign(hor, -1);
    mV.assign(ver, -1);
    mH.assign(hor, -1);
    for (int i = 0; i < ver; i++) {
        mk.assign(ver, 0);

        rs += try_kuhn(i);
    }

    cout << rs << el;
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    #ifdef _LOCAL
        in("input.txt");

        int t = 1;
//        cin >> t;
        for (int i = 1; i <= t; i++) {
            cout << "Test #" << i << elf;

            clock_t start_time = clock();

            solve();

            cerr.precision(4); cerr << fixed;
            cerr << elf;
            cerr << "Time :: " << ld(clock() - start_time) / CLOCKS_PER_SEC << elf;

            cout << elf;
        }
    #else
        int t = 1;
//        cin >> t;

        while (t--) {
            solve();
            cout << el;
        }
    #endif
}

• Subtask 1: 9 / 18
• Subtask 2: 16 / 32
• Subtask 3: 30 / 60