Submission #1043186

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1043186	2024-08-04T04:04:41 Z	ezGeometry	Tracks in the Snow (BOI13_tracks)	C++14	100 / 100	979 ms	110624 KB

tracks

#include <iostream>
#include <vector>
#include <algorithm>
#include <deque>

using namespace std;

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

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

	vector<vector<char>> grid(n + 2, vector<char>(m + 2, '.'));

	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			cin >> grid[i][j];
		}
	}

	vector<vector<int>> bfs(n + 2, vector<int>(m + 2, 1e9));
	bfs[1][1] = 1;

	deque<pair<int, int>> cur;
	cur.push_back(make_pair(1, 1));

	while (cur.size()) {
		auto c = cur.front();
		cur.pop_front();

		for (int i = 0; i < 4; i++) {
			int nx = c.first + dx[i];
			int ny = c.second + dy[i];

			int w = 1;
			if (grid[nx][ny] == grid[c.first][c.second]) {
				w = 0;
			}
			if (grid[nx][ny] == '.') {
				w = 1e9;
			}

			if (w != 1e9) {
				if (bfs[nx][ny] > bfs[c.first][c.second] + w) {
					bfs[nx][ny] = bfs[c.first][c.second] + w;
					if (w == 1) {
						cur.push_back(make_pair(nx, ny));
					}
					else {
						cur.push_front(make_pair(nx, ny));
					}
				}
			}
		}
	}

	int ans = 1;

	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			if (grid[i][j] != '.') {
				ans = max(ans, bfs[i][j]);
			}
		}
	}

	cout << ans << endl;
}

Subtask #1

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	1624 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	1 ms	348 KB	Output is correct
4	Correct	7 ms	1372 KB	Output is correct
5	Correct	4 ms	860 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	1 ms	348 KB	Output is correct
8	Correct	1 ms	348 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	2 ms	604 KB	Output is correct
11	Correct	2 ms	604 KB	Output is correct
12	Correct	4 ms	860 KB	Output is correct
13	Correct	3 ms	860 KB	Output is correct
14	Correct	3 ms	860 KB	Output is correct
15	Correct	12 ms	1628 KB	Output is correct
16	Correct	12 ms	1628 KB	Output is correct
17	Correct	10 ms	1624 KB	Output is correct
18	Correct	7 ms	1372 KB	Output is correct

Subtask #2

70.0 / 70.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	2 ms	860 KB	Output is correct
2	Correct	58 ms	8152 KB	Output is correct
3	Correct	520 ms	78932 KB	Output is correct
4	Correct	140 ms	18768 KB	Output is correct
5	Correct	315 ms	44708 KB	Output is correct
6	Correct	979 ms	92880 KB	Output is correct
7	Correct	2 ms	1112 KB	Output is correct
8	Correct	3 ms	860 KB	Output is correct
9	Correct	2 ms	756 KB	Output is correct
10	Correct	2 ms	604 KB	Output is correct
11	Correct	2 ms	860 KB	Output is correct
12	Correct	1 ms	348 KB	Output is correct
13	Correct	59 ms	8188 KB	Output is correct
14	Correct	34 ms	4932 KB	Output is correct
15	Correct	33 ms	5212 KB	Output is correct
16	Correct	27 ms	3420 KB	Output is correct
17	Correct	159 ms	20340 KB	Output is correct
18	Correct	129 ms	20036 KB	Output is correct
19	Correct	131 ms	18776 KB	Output is correct
20	Correct	112 ms	17236 KB	Output is correct
21	Correct	295 ms	46276 KB	Output is correct
22	Correct	311 ms	44624 KB	Output is correct
23	Correct	305 ms	38484 KB	Output is correct
24	Correct	311 ms	45012 KB	Output is correct
25	Correct	563 ms	78948 KB	Output is correct
26	Correct	507 ms	110624 KB	Output is correct
27	Correct	674 ms	107544 KB	Output is correct
28	Correct	786 ms	92880 KB	Output is correct
29	Correct	787 ms	93660 KB	Output is correct
30	Correct	752 ms	97952 KB	Output is correct
31	Correct	538 ms	51284 KB	Output is correct
32	Correct	650 ms	97052 KB	Output is correct