Submission #899415

#	Time	Username	Problem	Language	Result	Execution time	Memory
899415		LiuBruh	Maze (JOI23_ho_t3)	C++17	8 / 100	815 ms	870832 KiB

Main

#include <bits/stdc++.h>

#define int long long
#define F first
#define S second
#define sz(v) (int)v.size()
using namespace std;

const int INF = (int)1e18 + 5;

const int dx[4] = {0, 0, 1, -1};
const int dy[4] = {1, -1, 0, 0};

int r, c, n;
int sx, sy, tx, ty;
vector<vector<int>> g, dis, vis;
vector<vector<vector<int>>> e;

bool out(int x, int y) {
    return min(x, y) < 1 or x > r or y > c;
}

void solve() {
    cin >> r >> c >> n >> sx >> sy >> tx >> ty;

    g = vector<vector<int>> (r + 5, vector<int> (c + 5));
    e = vector<vector<vector<int>>> (r + 5, vector<vector<int>> (c + 5, vector<int> (4)));
    dis = vector<vector<int>> (r + 5, vector<int> (c + 5));
    vis = vector<vector<int>> (r + 5, vector<int> (c + 5));

    for (int i = 1; i <= r; i++) {
        for (int j = 1; j <= c; j++) {
            char ch;  cin >> ch;
            g[i][j] = (ch == '.');
        }
    }
    for (int i = 1; i <= r; i++) {
        for (int j = 1; j <= c; j++) {
            int nx, ny;
            for (int k = 0; k < 4; k++) {
                nx = i + dx[k];
                ny = j + dy[k];
                if (!out(nx, ny)) {
                    e[i][j][k] = (g[nx][ny] == 0);
                }
            }
        }
    }

    deque<pair<pair<int, int>, int>> dq;
    dq.push_back({{sx, sy}, 0});
    vis[sx][sy] = true;

    while (!dq.empty()) {
        auto [coo, d] = dq.front();  dq.pop_front();
        auto [x, y] = coo;
        dis[x][y] = d;

        int nx, ny;
        for (int k = 0; k < 4; k++) {
            nx = x + dx[k], ny = y + dy[k];
            if (out(nx, ny) or vis[nx][ny]) continue;
            vis[nx][ny] = true;
            if (e[x][y][k] == 0) {
                dq.push_front({{nx, ny}, d});
            } else {
                dq.push_back({{nx, ny}, d + 1});
            }
        }
    }

    cout << dis[tx][ty] << '\n';
}

signed main() {
    ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);

    solve();

    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 0 / 19
• Subtask 3: 0 / 16
• Subtask 4: 0 / 19
• Subtask 5: 0 / 5
• Subtask 6: 0 / 19
• Subtask 7: 0 / 8
• Subtask 8: 0 / 6