제출 #374226

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
374226		daduam	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	1750 ms	186944 KiB

tracks

#include <bits/stdc++.h>
using namespace std;

int main() {
    int n, m;
    cin >> n >> m;
    vector<vector<char>> meadow(n, vector<char>(m));
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            cin >> meadow[i][j];
        }
    }

    vector<vector<int>> d(n, vector<int>(m));
    vector<vector<int>> used(n, vector<int>(m));
    deque<pair<int, int>> q;
    q.push_front({0, 0});
    used[0][0] = true;
    d[0][0] = 1;

    while (!q.empty()) {
        auto [r, c] = q.front();
        q.pop_front();
        static vector<pair<int, int>> dirs = {{-1, 0}, {0, 1}, {1, 0}, {0, -1}};
        for (auto [x, y] : dirs) {
            x += r, y += c;
            if (x >= 0 && x < n && y >= 0 && y < m && !used[x][y] &&
                meadow[x][y] != '.') {
                if (meadow[r][c] != meadow[x][y]) {
                    d[x][y] = d[r][c] + 1;
                    q.push_back({x, y});
                } else {
                    d[x][y] = d[r][c];
                    q.push_front({x, y});
                }
                used[x][y] = true;
            }
        }
    }

    int rv = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            rv = max(rv, d[i][j]);
        }
    }
    cout << rv << "\n";
}

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70