Submission #1253839

#	Time	Username	Problem	Language	Result	Execution time	Memory
1253839		shawnchang51	Maze (JOI23_ho_t3)	C++17	Compilation error	0 ms	0 KiB

Main

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

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

```
int R, C, N;
cin >> R >> C >> N;

int Sr, Sc, Gr, Gc;
cin >> Sr >> Sc >> Gr >> Gc;
Sr--; Sc--; Gr--; Gc--; // Convert to 0-indexed

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

// BFS with distance representing minimum stamp operations needed
vector<vector<int>> dist(R, vector<int>(C, -1));
queue<pair<int, int>> q;

// Start BFS from the starting position
dist[Sr][Sc] = 0;
q.push({Sr, Sc});

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

// First, find all cells reachable with 0 operations (just white cell traversal)
while (!q.empty()) {
    auto [x, y] = q.front();
    q.pop();
    
    for (int dir = 0; dir < 4; dir++) {
        int nx = x + dx[dir];
        int ny = y + dy[dir];
        
        if (nx >= 0 && nx < R && ny >= 0 && ny < C && 
            dist[nx][ny] == -1 && grid[nx][ny] == '.') {
            dist[nx][ny] = 0;
            q.push({nx, ny});
        }
    }
}

if (dist[Gr][Gc] == 0) {
    cout << 0 << endl;
    return 0;
}

// Now use BFS for stamp operations
for (int ops = 1; ops <= 50; ops++) {
    vector<pair<int, int>> newCells;
    
    // Try all possible stamp positions
    for (int a = 0; a <= R - N; a++) {
        for (int b = 0; b <= C - N; b++) {
            // Check if this stamp connects to any cell reachable with ops-1 operations
            bool connects = false;
            for (int i = a; i < a + N && !connects; i++) {
                for (int j = b; j < b + N && !connects; j++) {
                    if (dist[i][j] != -1 && dist[i][j] < ops) {
                        connects = true;
                    }
                }
            }
            
            if (connects) {
                // This stamp can be used, mark all cells in stamp region as reachable with ops operations
                for (int i = a; i < a + N; i++) {
                    for (int j = b; j < b + N; j++) {
                        if (dist[i][j] == -1) {
                            dist[i][j] = ops;
                            newCells.push_back({i, j});
                        }
                    }
                }
            }
        }
    }
    
    // From newly reachable cells, do BFS to find other reachable white cells
    queue<pair<int, int>> bfsQ;
    for (auto& cell : newCells) {
        bfsQ.push(cell);
    }
    
    while (!bfsQ.empty()) {
        auto [x, y] = bfsQ.front();
        bfsQ.pop();
        
        for (int dir = 0; dir < 4; dir++) {
            int nx = x + dx[dir];
            int ny = y + dy[dir];
            
            if (nx >= 0 && nx < R && ny >= 0 && ny < C && 
                dist[nx][ny] == -1 && grid[nx][ny] == '.') {
                dist[nx][ny] = ops;
                bfsQ.push({nx, ny});
            }
        }
    }
    
    if (dist[Gr][Gc] == ops) {
        cout << ops << endl;
        return 0;
    }
}

cout << dist[Gr][Gc] << endl;
return 0;
```

}

Compilation message (stderr)

Main.cpp:8:1: error: stray '`' in program
    8 | ```
      | ^
Main.cpp:8:2: error: stray '`' in program
    8 | ```
      |  ^
Main.cpp:8:3: error: stray '`' in program
    8 | ```
      |   ^
Main.cpp:115:1: error: stray '`' in program
  115 | ```
      | ^
Main.cpp:115:2: error: stray '`' in program
  115 | ```
      |  ^
Main.cpp:115:3: error: stray '`' in program
  115 | ```
      |   ^