Submission #729372

#	Time	Username	Problem	Language	Result	Execution time	Memory
729372		Pring	Dango Maker (JOI18_dango_maker)	C++14	13 / 100	2070 ms	468 KiB

dango_maker

#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")

#define int long long
typedef pair<int, int> pii;

const int MXN = 3000;
int n, m, ans = 0;
string s[MXN];
vector<vector<pii>> tango;
bitset<MXN> b[MXN];

void GET_TANGO() {
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m - 2; j++) {
            if (s[i][j] == 'R' && s[i][j + 1] == 'G' && s[i][j + 2] == 'W') {
                tango.push_back({{i, j}, {i, j + 1}, {i, j + 2}});
            }
            // if (s[i][j] == 'W' && s[i][j + 1] == 'G' && s[i][j + 2] == 'R') {
            //     tango.push_back({{i, j}, {i, j + 1}, {i, j + 2}});
            // }
        }
    }
    for (int j = 0; j < m; j++) {
        for (int i = 0; i < n - 2; i++) {
            if (s[i][j] == 'R' && s[i + 1][j] == 'G' && s[i + 2][j] == 'W') {
                tango.push_back({{i, j}, {i + 1, j}, {i + 2, j}});
            }
            // if (s[i][j] == 'W' && s[i + 1][j] == 'G' && s[i + 2][j] == 'R') {
            //     tango.push_back({{i, j}, {i + 1, j}, {i + 2, j}});
            // }
        }
    }
}

void DFS(int id, int now) {
    if (id == tango.size()) {
        ans = max(ans, now);
        return;
    }
    bool flag = true;
    for (int i = 0; flag && i < 3; i++) {
        if (b[tango[id][i].first][tango[id][i].second]) {
            flag = false;
        }
    }
    if (flag) {
        for (int i = 0; flag && i < 3; i++) {
            b[tango[id][i].first][tango[id][i].second] = true;
        }
        DFS(id + 1, now + 1);
        for (int i = 0; flag && i < 3; i++) {
            b[tango[id][i].first][tango[id][i].second] = false;
        }
    }
    DFS(id + 1, now);
}

int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m;
    for (int i = 0; i < n; i++) cin >> s[i];
    GET_TANGO();
    // for (auto &i : tango) {
    //     for (auto &j : i) cout << j.first << ' ' << j.second << endl;
    //     cout << endl;
    // }
    DFS(0, 0);
    cout << ans << endl;
    return 0;
}

Compilation message (stderr)

dango_maker.cpp: In function 'void DFS(long long int, long long int)':
dango_maker.cpp:38:12: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::vector<std::pair<long long int, long long int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     if (id == tango.size()) {
      |         ~~~^~~~~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 0 / 20
• Subtask 3: 0 / 67