Submission #756081

#	Time	Username	Problem	Language	Result	Execution time	Memory
756081		Kihihihi	Dango Maker (JOI18_dango_maker)	C++17	100 / 100	1463 ms	234600 KiB

dango_maker

#include <iostream>
#include <iomanip>
#include <algorithm>
#include <numeric>
#include <cmath>
#include <cassert>
#include <ctime>
#include <chrono>
#include <cstdio>
#include <random>
#include <vector>
#include <string>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <deque>
#include <queue>
#include <bitset>
#include <list>
#include <fstream>
#include <functional>
#include <complex>
using namespace std;
mt19937_64 rnd(chrono::steady_clock::now().time_since_epoch().count());

const int INF = 1e9, MOD = 1e9 + 7, MOD2 = 998244353, LOG = 18;
const long double EPS = 1e-9, PI = acos(-1);

bool check_vert(vector<string>& t, int x, int y)
{
    if (x < 0 || x >= (int)t.size() - 2)
    {
        return false;
    }

    return t[x][y] == 'R' && t[x + 1][y] == 'G' && t[x + 2][y] == 'W';
}

bool kuhn(vector<vector<int>>& g, int v, vector<int>& mt, vector<int>& used, int tmr)
{
    if (used[v] == tmr)
    {
        return false;
    }

    used[v] = tmr;
    for (auto& i : g[v])
    {
        if (mt[i] == -1 || kuhn(g, mt[i], mt, used, tmr))
        {
            mt[i] = v;
            return true;
        }
    }
    return false;
};

void dfs(vector<vector<int>>& g, int v, vector<int>& mt, vector<bool>& visl, vector<bool>& visr)
{
    visl[v] = true;
    for (auto& i : g[v])
    {
        if (mt[i] == v || visr[i])
        {
            continue;
        }

        visr[i] = true;
        if (mt[i] != -1 && !visl[mt[i]])
        {
            dfs(g, mt[i], mt, visl, visr);
        }
    }
};

void solve()
{
    int n, m;
    vector<string> t;
    cin >> n >> m;
    t.resize(n);
    for (int i = 0; i < n; i++)
    {
        cin >> t[i];
    }

    vector<vector<int>> ver_idx(n, vector<int>(m, -1));
    int rsz = 0;
    for (int i = 0; i < n - 2; i++)
    {
        for (int j = 0; j < m; j++)
        {
            if (check_vert(t, i, j))
            {
                ver_idx[i][j] = rsz++;
            }
        }
    }

    vector<vector<int>> g;
    vector<int> mt(rsz, -1);
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m - 2; j++)
        {
            if (t[i][j] != 'R' || t[i][j + 1] != 'G' || t[i][j + 2] != 'W')
            {
                continue;
            }

            g.push_back({});
            if (check_vert(t, i, j))
            {
                g.back().push_back(ver_idx[i][j]);
            }
            if (check_vert(t, i - 1, j + 1))
            {
                g.back().push_back(ver_idx[i - 1][j + 1]);
            }
            if (check_vert(t, i - 2, j + 2))
            {
                g.back().push_back(ver_idx[i - 2][j + 2]);
            }
        }
    }
    int lsz = g.size();

    int tmr = 0;
    vector<int> used(lsz, -1);

    for (int i = 0; i < lsz; i++)
    {
        kuhn(g, i, mt, used, tmr);
        tmr++;
    }

    vector<bool> in_mt(lsz);
    for (int i = 0; i < rsz; i++)
    {
        if (mt[i] == -1)
        {
            continue;
        }

        in_mt[mt[i]] = true;
    }
    vector<bool> visl(lsz), visr(rsz);

    for (int i = 0; i < lsz; i++)
    {
        if (in_mt[i] || visl[i])
        {
            continue;
        }

        dfs(g, i, mt, visl, visr);
    }

    int ans = count(visl.begin(), visl.end(), true) + count(visr.begin(), visr.end(), false);
    cout << ans << "\n";
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    srand(time(NULL));

    int tst = 1;
    //cin >> tst;
    while (tst--)
    {
        solve();
    }

    return 0;
}

/*
<3 <3 <3 <3 <3 <3 <3 <3 <3 <3 <3 <3 <3
⠀⠀⠀⠀⠀⠀⠀⠀⠀⣠⠤⠖⠚⢉⣩⣭⡭⠛⠓⠲⠦⣄⡀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⢀⡴⠋⠁⠀⠀⠊⠀⠀⠀⠀⠀⠀⠀⠀⠀⠉⠳⢦⡀⠀⠀⠀⠀
⠀⠀⠀⠀⢀⡴⠃⢀⡴⢳⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠙⣆⠀⠀⠀
⠀⠀⠀⠀⡾⠁⣠⠋⠀⠈⢧⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⢧⠀⠀
⠀⠀⠀⣸⠁⢰⠃⠀⠀⠀⠈⢣⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⣇⠀
⠀⠀⠀⡇⠀⡾⡀⠀⠀⠀⠀⣀⣹⣆⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢹⠀
⠀⠀⢸⠃⢀⣇⡈⠀⠀⠀⠀⠀⠀⢀⡑⢄⡀⢀⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⡇
⠀⠀⢸⠀⢻⡟⡻⢶⡆⠀⠀⠀⠀⡼⠟⡳⢿⣦⡑⢄⠀⠀⠀⠀⠀⠀⠀⠀⢸⡇
⠀⠀⣸⠀⢸⠃⡇⢀⠇⠀⠀⠀⠀⠀⡼⠀⠀⠈⣿⡗⠂⠀⠀⠀⠀⠀⠀⠀⢸⠁
⠀⠀⡏⠀⣼⠀⢳⠊⠀⠀⠀⠀⠀⠀⠱⣀⣀⠔⣸⠁⠀⠀⠀⠀⠀⠀⠀⢠⡟⠀
⠀⠀⡇⢀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠠⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⢸⠃⠀
⠀⢸⠃⠘⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⠁⠀⠀⢀⠀⠀⠀⠀⠀⣾⠀⠀
⠀⣸⠀⠀⠹⡄⠀⠀⠈⠁⠀⠀⠀⠀⠀⠀⠀⡞⠀⠀⠀⠸⠀⠀⠀⠀⠀⡇⠀⠀
⠀⡏⠀⠀⠀⠙⣆⠀⠀⠀⠀⠀⠀⠀⢀⣠⢶⡇⠀⠀⢰⡀⠀⠀⠀⠀⠀⡇⠀⠀
⢰⠇⡄⠀⠀⠀⡿⢣⣀⣀⣀⡤⠴⡞⠉⠀⢸⠀⠀⠀⣿⡇⠀⠀⠀⠀⠀⣧⠀⠀
⣸⠀⡇⠀⠀⠀⠀⠀⠀⠉⠀⠀⠀⢹⠀⠀⢸⠀⠀⢀⣿⠇⠀⠀⠀⠁⠀⢸⠀⠀
⣿⠀⡇⠀⠀⠀⠀⠀⢀⡤⠤⠶⠶⠾⠤⠄⢸⠀⡀⠸⣿⣀⠀⠀⠀⠀⠀⠈⣇⠀
⡇⠀⡇⠀⠀⡀⠀⡴⠋⠀⠀⠀⠀⠀⠀⠀⠸⡌⣵⡀⢳⡇⠀⠀⠀⠀⠀⠀⢹⡀
⡇⠀⠇⠀⠀⡇⡸⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠙⠮⢧⣀⣻⢂⠀⠀⠀⠀⠀⠀⢧
⣇⠀⢠⠀⠀⢳⠇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⡎⣆⠀⠀⠀⠀⠀⠘
⢻⠀⠈⠰⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠰⠘⢮⣧⡀⠀⠀⠀⠀
⠸⡆⠀⠀⠇⣾⠀⠀⠀⠀⠀⠀⠀⠀⠀⢠⠆⠀⠀⠀⠀⠀⠀⠀⠙⠳⣄⡀⢢⡀
<3 <3 <3 <3 <3 <3 <3 <3 <3 <3 <3 <3 <3
*/

• Subtask 1: 13 / 13
• Subtask 2: 20 / 20
• Subtask 3: 67 / 67