Submission #1062303

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1062303	2024-08-17T02:46:57 Z	danielzhu	Tracks in the Snow (BOI13_tracks)	C++17	86.875 / 100	2000 ms	70736 KB

tracks

#include <bits/stdc++.h>
using namespace std;
int H, W;
char grid[4001][4001];
vector<pair<int,int>> dir = {{0, 1}, {1, 0}, {0, -1}, {-1, 0}};

void bfs(set<pair<int,int>> &from, set<pair<int,int>> &to, char cc){
	while(!from.empty()){
			auto temp = from.begin();
			from.erase(from.begin());
			grid[temp->first][temp->second] = '.';
			from.erase({temp->first, temp->second});
			int x = temp->first, y = temp->second;
			for(auto [dx, dy] : dir){
				if(x+dx > -1 && x+dx < H && y+dy > -1 && y+dy < W && grid[x+dx][y+dy] != '.'){
					if(grid[x+dx][y+dy] != cc) to.insert({x+dx, y+dy});
					else from.insert({x+dx, y+dy});
				}
			}
	}
}

int main(){
	cin>>H>>W;
	for(int i = 0; i < H; i++){
		string s; cin>>s;
		for(int j = 0; j < W; j++){
			grid[i][j] = s[j];
		}
	}
	int x = 0, y = 0, ans = 0;
	char cc = grid[0][0];
	set<pair<int,int>> F, R;
	if(cc == 'F') F.insert({0,0});
	else R.insert({0,0});
	while(true){
		if(cc == 'F' && F.empty()) break;
		if(cc == 'R' && R.empty()) break;
		if(cc == 'F')
			bfs(F, R, cc);
		else if(cc == 'R')
			bfs(R, F, cc);
		ans++;
		if(cc == 'F') cc = 'R';
		else if(cc == 'R') cc = 'F';
	}
	cout<<ans<<endl;
	return 0;
}

Compilation message

tracks.cpp: In function 'int main()':
tracks.cpp:31:6: warning: unused variable 'x' [-Wunused-variable]
   31 |  int x = 0, y = 0, ans = 0;
      |      ^
tracks.cpp:31:13: warning: unused variable 'y' [-Wunused-variable]
   31 |  int x = 0, y = 0, ans = 0;
      |             ^

Subtask #1

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	49 ms	2904 KB	Output is correct
2	Correct	1 ms	348 KB	Output is correct
3	Correct	1 ms	2652 KB	Output is correct
4	Correct	27 ms	3328 KB	Output is correct
5	Correct	4 ms	2652 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	1 ms	2652 KB	Output is correct
8	Correct	1 ms	2652 KB	Output is correct
9	Correct	1 ms	2652 KB	Output is correct
10	Correct	5 ms	2648 KB	Output is correct
11	Correct	7 ms	2900 KB	Output is correct
12	Correct	17 ms	2848 KB	Output is correct
13	Correct	4 ms	2476 KB	Output is correct
14	Correct	5 ms	2652 KB	Output is correct
15	Correct	33 ms	2652 KB	Output is correct
16	Correct	48 ms	2980 KB	Output is correct
17	Correct	18 ms	2648 KB	Output is correct
18	Correct	27 ms	3420 KB	Output is correct

Subtask #2

56.875 / 70.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	3 ms	15196 KB	Output is correct
2	Correct	110 ms	6752 KB	Output is correct
3	Correct	465 ms	15956 KB	Output is correct
4	Correct	108 ms	8788 KB	Output is correct
5	Correct	257 ms	12892 KB	Output is correct
6	Execution timed out	2073 ms	69460 KB	Time limit exceeded
7	Correct	3 ms	15960 KB	Output is correct
8	Correct	3 ms	15196 KB	Output is correct
9	Correct	5 ms	620 KB	Output is correct
10	Correct	1 ms	348 KB	Output is correct
11	Correct	3 ms	15708 KB	Output is correct
12	Correct	1 ms	2652 KB	Output is correct
13	Correct	104 ms	6764 KB	Output is correct
14	Correct	60 ms	4700 KB	Output is correct
15	Correct	24 ms	4700 KB	Output is correct
16	Correct	58 ms	2740 KB	Output is correct
17	Correct	264 ms	8804 KB	Output is correct
18	Correct	93 ms	8784 KB	Output is correct
19	Correct	132 ms	8788 KB	Output is correct
20	Correct	104 ms	8788 KB	Output is correct
21	Correct	261 ms	12880 KB	Output is correct
22	Correct	262 ms	12880 KB	Output is correct
23	Correct	525 ms	11052 KB	Output is correct
24	Correct	225 ms	12888 KB	Output is correct
25	Correct	372 ms	15972 KB	Output is correct
26	Correct	1605 ms	15116 KB	Output is correct
27	Execution timed out	2037 ms	25424 KB	Time limit exceeded
28	Execution timed out	2029 ms	70736 KB	Time limit exceeded
29	Execution timed out	2044 ms	63856 KB	Time limit exceeded
30	Execution timed out	2058 ms	58728 KB	Time limit exceeded
31	Execution timed out	2063 ms	17244 KB	Time limit exceeded
32	Correct	1951 ms	20308 KB	Output is correct