Submission #730175

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
730175	2023-04-25T11:33:32 Z	a_aguilo	Tracks in the Snow (BOI13_tracks)	C++14	100 / 100	790 ms	123184 KB

tracks

#include<bits/stdc++.h>

using namespace std;

int H, W;
vector<string> snow;
vector<vector<int>> distances;

int bfs(){
	deque<int> DQ;
	distances[0][0] = 1;
	int ans = 1;
	DQ.push_back(0);
	while(!DQ.empty()){
		int actual = DQ.front(); DQ.pop_front();
		int x = actual/W;
		int y = actual - W*x;
		ans = max(ans, distances[x][y]);
		if(x){
			if(distances[x-1][y] == -1){
				if(snow[x-1][y] == snow[x][y]){
					distances[x-1][y] = distances[x][y];
					DQ.push_front((x-1)*W + y);
				}
				else if (snow[x-1][y] != '.'){
					distances[x-1][y] = distances[x][y]+1;
					DQ.push_back((x-1)*W + y);
				}
			}
		}
		if(y){
			if(distances[x][y-1] == -1){
				if(snow[x][y-1] == snow[x][y]){
					distances[x][y-1] = distances[x][y];
					DQ.push_front((x)*W + y-1);
				}
				else if (snow[x][y-1] != '.'){
					distances[x][y-1] = distances[x][y]+1;
					DQ.push_back((x)*W + y-1);
				}
			}
		}
		if(x < (H-1)){
			if(distances[x+1][y] == -1){
				if(snow[x+1][y] == snow[x][y]){
					distances[x+1][y] = distances[x][y];
					DQ.push_front((x+1)*W + y);
				}
				else if (snow[x+1][y] != '.'){
					distances[x+1][y] = distances[x][y]+1;
					DQ.push_back((x+1)*W + y);
				}
			}
		}
		if(y < (W-1)){
			if(distances[x][y+1] == -1){
				if(snow[x][y+1] == snow[x][y]){
					distances[x][y+1] = distances[x][y];
					DQ.push_front((x)*W + y + 1);
				}
				else if (snow[x][y+1] != '.'){
					distances[x][y+1] = distances[x][y]+1;
					DQ.push_back((x)*W + y + 1);
				}
			}
		}
	}
	return ans;
}

int main(){
	cin >> H >> W;
	snow = vector<string>(H);
	for(int i = 0; i < H; ++i)cin >> snow[i];
	distances = vector<vector<int>>(H, vector<int>(W, -1));
	cout << bfs()<< endl;
	return 0;
}

Subtask #1

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	13 ms	2004 KB	Output is correct
2	Correct	1 ms	300 KB	Output is correct
3	Correct	1 ms	300 KB	Output is correct
4	Correct	11 ms	1336 KB	Output is correct
5	Correct	4 ms	836 KB	Output is correct
6	Correct	1 ms	300 KB	Output is correct
7	Correct	1 ms	212 KB	Output is correct
8	Correct	1 ms	340 KB	Output is correct
9	Correct	1 ms	340 KB	Output is correct
10	Correct	3 ms	692 KB	Output is correct
11	Correct	3 ms	468 KB	Output is correct
12	Correct	5 ms	792 KB	Output is correct
13	Correct	4 ms	792 KB	Output is correct
14	Correct	4 ms	792 KB	Output is correct
15	Correct	16 ms	2024 KB	Output is correct
16	Correct	14 ms	2004 KB	Output is correct
17	Correct	11 ms	1876 KB	Output is correct
18	Correct	9 ms	1364 KB	Output is correct

Subtask #2

70.0 / 70.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	3 ms	724 KB	Output is correct
2	Correct	60 ms	10376 KB	Output is correct
3	Correct	489 ms	108872 KB	Output is correct
4	Correct	116 ms	25872 KB	Output is correct
5	Correct	299 ms	55844 KB	Output is correct
6	Correct	762 ms	115836 KB	Output is correct
7	Correct	3 ms	692 KB	Output is correct
8	Correct	3 ms	692 KB	Output is correct
9	Correct	3 ms	596 KB	Output is correct
10	Correct	2 ms	468 KB	Output is correct
11	Correct	3 ms	724 KB	Output is correct
12	Correct	1 ms	340 KB	Output is correct
13	Correct	61 ms	10376 KB	Output is correct
14	Correct	34 ms	6448 KB	Output is correct
15	Correct	31 ms	7044 KB	Output is correct
16	Correct	27 ms	4148 KB	Output is correct
17	Correct	150 ms	27860 KB	Output is correct
18	Correct	131 ms	27544 KB	Output is correct
19	Correct	124 ms	25800 KB	Output is correct
20	Correct	102 ms	23856 KB	Output is correct
21	Correct	278 ms	57668 KB	Output is correct
22	Correct	296 ms	55844 KB	Output is correct
23	Correct	311 ms	47876 KB	Output is correct
24	Correct	286 ms	56712 KB	Output is correct
25	Correct	559 ms	108956 KB	Output is correct
26	Correct	499 ms	98824 KB	Output is correct
27	Correct	720 ms	123184 KB	Output is correct
28	Correct	790 ms	115868 KB	Output is correct
29	Correct	764 ms	116172 KB	Output is correct
30	Correct	719 ms	116984 KB	Output is correct
31	Correct	587 ms	62796 KB	Output is correct
32	Correct	653 ms	118132 KB	Output is correct