제출 #1174629

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1174629		viwlesxq	Tracks in the Snow (BOI13_tracks)	C++20	100 / 100	430 ms	112152 KiB

tracks

#include <bits/stdc++.h>

using namespace std;

//#define int long long
#define all(x) x.begin(), x.end()

template<class A, class B>
bool chmin(A &a, const B &b) {
    return a > b ? (a = b) == b : false;
} template<class A, class B>
bool chmax(A &a, const B &b) {
    return a < b ? (a = b) == b : false;
}

const int dx[] = {-1, 1, 0, 0};
const int dy[] = {0, 0, -1, 1};

signed main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int n, m; cin >> n >> m;

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

    auto in = [&](int i, int j) {
        return i >= 0 && i < n && j >= 0 && j < m;
    };

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

    while (!q.empty()) {
        auto [i, j] = q.front();
        q.pop_front();

        for (int k = 0; k < 4; ++k) {
            int x = i + dx[k];
            int y = j + dy[k];

            if (in(x, y) && d[x][y] == -1 && s[x][y] != '.') {
                if (s[x][y] == s[i][j]) {
                    d[x][y] = d[i][j];
                    q.push_front({x, y});
                } else {
                    d[x][y] = d[i][j] + 1;
                    q.push_back({x, y});
                }
            }
        }
    }

    int res = 0;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            chmax(res, d[i][j]);
        }
    }

    cout << res;
}

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