oj.uz

Submission #1101238

# Submission time Handle Problem Language Result Execution time Memory
1101238 2024-10-15T20:38:51 Z JohnnyVenturas Tracks in the Snow (BOI13_tracks) C++17
100 / 100
 1555 ms 445712 KB 
#include <bits/stdc++.h>
using namespace std;
int rows[]{1, -1, 0, 0};
int cols[]{0, 0, 1, -1};

struct inf {
    int r, c, d;
    inf() {}
    inf(int r, int c, int d) : r(r), c(c), d(d) {}
};

void bfs(vector<vector<char>> &grid, vector<vector<int>> &distances) {
    deque<inf> dq;
    dq.push_front(inf(0, 0, 1));

    while (!dq.empty()) {
        auto top = dq.front();
        dq.pop_front();

        if (distances[top.r][top.c] != 1e9)
            continue;

        distances[top.r][top.c] = top.d;

        for (int i = 0; i < 4; ++i) {
            int nrow = top.r + rows[i];
            int ncol = top.c + cols[i];
            if (nrow < 0 || ncol < 0 || nrow == grid.size() ||
                ncol == grid[0].size())
                continue;
            if (grid[nrow][ncol] == '.')
                continue;
            if (grid[nrow][ncol] != grid[top.r][top.c]) {
                dq.push_back(inf(nrow, ncol, top.d + 1));
            } else {
                dq.push_front(inf(nrow, ncol, top.d));
            }
        }
    }
}

int main() {
    int n, m;
    cin >> n >> m;

    vector<vector<char>> grid(n, vector<char>(m, '.'));

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            cin >> grid[i][j];
        }
    }

    vector<vector<int>> distances(n, vector<int>(m, 1e9));

    bfs(grid, distances);

    int max_value = 0;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
                                                if(grid[i][j] == '.') continue;
            max_value = max(max_value, distances[i][j]);
        }
    }
    cout << max_value << "\n";
}

Compilation message

tracks.cpp: In function 'void bfs(std::vector<std::vector<char> >&, std::vector<std::vector<int> >&)':
tracks.cpp:28:46: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |             if (nrow < 0 || ncol < 0 || nrow == grid.size() ||
      |                                         ~~~~~^~~~~~~~~~~~~~
tracks.cpp:29:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |                 ncol == grid[0].size())
      |                 ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 2128 KB Output is correct
2 Correct 1 ms 336 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 13 ms 1832 KB Output is correct
5 Correct 5 ms 848 KB Output is correct
6 Correct 1 ms 336 KB Output is correct
7 Correct 1 ms 508 KB Output is correct
8 Correct 2 ms 336 KB Output is correct
9 Correct 2 ms 396 KB Output is correct
10 Correct 4 ms 848 KB Output is correct
11 Correct 4 ms 848 KB Output is correct
12 Correct 8 ms 1360 KB Output is correct
13 Correct 5 ms 848 KB Output is correct
14 Correct 6 ms 860 KB Output is correct
15 Correct 22 ms 2128 KB Output is correct
16 Correct 21 ms 2128 KB Output is correct
17 Correct 15 ms 1940 KB Output is correct
18 Correct 14 ms 2044 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 848 KB Output is correct
2 Correct 80 ms 9552 KB Output is correct
3 Correct 664 ms 94560 KB Output is correct
4 Correct 171 ms 22600 KB Output is correct
5 Correct 362 ms 53320 KB Output is correct
6 Correct 1555 ms 146224 KB Output is correct
7 Correct 3 ms 848 KB Output is correct
8 Correct 3 ms 1020 KB Output is correct
9 Correct 4 ms 848 KB Output is correct
10 Correct 3 ms 592 KB Output is correct
11 Correct 3 ms 1016 KB Output is correct
12 Correct 1 ms 336 KB Output is correct
13 Correct 82 ms 9540 KB Output is correct
14 Correct 46 ms 5704 KB Output is correct
15 Correct 40 ms 6164 KB Output is correct
16 Correct 40 ms 4176 KB Output is correct
17 Correct 219 ms 24392 KB Output is correct
18 Correct 171 ms 23864 KB Output is correct
19 Correct 171 ms 22600 KB Output is correct
20 Correct 147 ms 20728 KB Output is correct
21 Correct 415 ms 55368 KB Output is correct
22 Correct 372 ms 53320 KB Output is correct
23 Correct 463 ms 46252 KB Output is correct
24 Correct 398 ms 53832 KB Output is correct
25 Correct 682 ms 94536 KB Output is correct
26 Correct 1300 ms 445712 KB Output is correct
27 Correct 1463 ms 235596 KB Output is correct
28 Correct 1523 ms 146396 KB Output is correct
29 Correct 1512 ms 142248 KB Output is correct
30 Correct 1441 ms 176736 KB Output is correct
31 Correct 880 ms 63048 KB Output is correct
32 Correct 1272 ms 188352 KB Output is correct