Submission #990781

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
990781	2024-05-31T10:40:23 Z	kfhjad	Tracks in the Snow (BOI13_tracks)	C++17	97.8125 / 100	736 ms	1048576 KB

tracks

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

int H, W;
vector<string> meadow;
vector<vector<int>> val;
queue<pair<int, int>> q;

int switches;
char animal;

bool cnt = false;

void dfs(int row, int col)
{
    if (row < 0 || col < 0 || row == H || col == W || meadow[row][col] == '.')
        return;
    
    if (val[row][col] != 0 && cnt)
        return;

    cnt = true;

    if (animal != meadow[row][col])
    {
        q.push({row, col});
        val[row][col] = switches + 1;
        return;
    }

    val[row][col] = switches;

    dfs(row + 1, col);
    dfs(row - 1, col);
    dfs(row, col + 1);
    dfs(row, col - 1);
}

int main()
{
    cin.tie(NULL) -> sync_with_stdio(false);
    cin >> H >> W;
    meadow.resize(H);
    val.resize(H, vector<int>(W));

    for (auto& i : meadow)
        cin >> i;
    
    q.push({0, 0});
    val[0][0] = 1;

    while (!q.empty())
    {
        auto [row, col] = q.front();
        q.pop();

        switches = val[row][col];
        animal = meadow[row][col];
        cnt = false;
        dfs(row, col);
    }
    
    int ans = 0;

    for (int i = 0; i < H; ++i)
        for (int j = 0; j < W; ++j)
            ans = max(ans, val[i][j]);

    cout << ans << endl;

    return 0;
}

/* stuff you should look for
 * int overflow, array bounds
 * special cases (n=1?)
 * do smth instead of nothing and stay organized
 * WRITE STUFF DOWN
 * DON'T GET STUCK ON ONE APPROACH
 */

Subtask #1

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	8 ms	1884 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	348 KB	Output is correct
4	Correct	5 ms	2396 KB	Output is correct
5	Correct	1 ms	976 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	0 ms	348 KB	Output is correct
8	Correct	0 ms	348 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	1 ms	860 KB	Output is correct
11	Correct	1 ms	860 KB	Output is correct
12	Correct	3 ms	860 KB	Output is correct
13	Correct	2 ms	860 KB	Output is correct
14	Correct	1 ms	860 KB	Output is correct
15	Correct	7 ms	2120 KB	Output is correct
16	Correct	8 ms	2024 KB	Output is correct
17	Correct	5 ms	1884 KB	Output is correct
18	Correct	6 ms	2396 KB	Output is correct

Subtask #2

67.8125 / 70.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	1116 KB	Output is correct
2	Correct	29 ms	10088 KB	Output is correct
3	Correct	156 ms	97364 KB	Output is correct
4	Correct	43 ms	23124 KB	Output is correct
5	Correct	126 ms	54864 KB	Output is correct
6	Correct	533 ms	154848 KB	Output is correct
7	Correct	1 ms	1112 KB	Output is correct
8	Correct	1 ms	1116 KB	Output is correct
9	Correct	1 ms	1232 KB	Output is correct
10	Correct	1 ms	860 KB	Output is correct
11	Correct	1 ms	1372 KB	Output is correct
12	Correct	1 ms	604 KB	Output is correct
13	Correct	27 ms	10032 KB	Output is correct
14	Correct	16 ms	5976 KB	Output is correct
15	Correct	10 ms	6492 KB	Output is correct
16	Correct	14 ms	4560 KB	Output is correct
17	Correct	73 ms	25116 KB	Output is correct
18	Correct	47 ms	24668 KB	Output is correct
19	Correct	45 ms	23224 KB	Output is correct
20	Correct	37 ms	21584 KB	Output is correct
21	Correct	95 ms	56660 KB	Output is correct
22	Correct	136 ms	54864 KB	Output is correct
23	Correct	153 ms	47448 KB	Output is correct
24	Correct	104 ms	55352 KB	Output is correct
25	Correct	208 ms	97392 KB	Output is correct
26	Runtime error	642 ms	1048576 KB	Execution killed with signal 9
27	Correct	706 ms	399432 KB	Output is correct
28	Correct	551 ms	154856 KB	Output is correct
29	Correct	546 ms	145244 KB	Output is correct
30	Correct	578 ms	203752 KB	Output is correct
31	Correct	354 ms	62960 KB	Output is correct
32	Correct	736 ms	425240 KB	Output is correct