Submission #1063714

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1063714	2024-08-18T00:05:23 Z	danielzhu	Tracks in the Snow (BOI13_tracks)	C++17	95.625 / 100	1896 ms	1048576 KB

tracks

#include <bits/stdc++.h>
using namespace std;
int H, W;
int grid[4001][4001], cc[4001][4001];
queue<pair<int,int>> q;
vector<pair<int,int>> dir = {{0, 1}, {1, 0}, {0, -1}, {-1, 0}};
 
void ff(int cur, int val){
	while(!q.empty()){
		auto temp = q.front();
		int x = temp.first, y = temp.second;
		q.pop();
		for(auto [dx, dy] : dir){
			if((x+dx > -1)&& (x+dx < H) && (y+dy > -1) && (y+dy < W) && (cc[x+dx][y+dy] == -1) && (grid[x+dx][y+dy] == cur)){
				cc[x+dx][y+dy] = val;
				q.push({x+dx, y+dy});
			}
		}
	}
}				
 
int main(){
	cin>>H>>W;
	memset(grid, 0, sizeof(grid));
	memset(cc, -1, sizeof(cc));
	for(int i = 0; i < H; i++){
		string s; cin>>s;
		for(int j = 0; j < W; j++){
			if(s[j] == 'F') grid[i][j] = 1;
			else if(s[j] == 'R') grid[i][j] = 2;
		}
	}
	int val = 0;
	for(int i = 0; i < H; i++){
		for(int j = 0; j < W; j++){
			if(cc[i][j] == -1 && grid[i][j] != 0){
				cc[i][j] = val;
				q.push({i,j});
				ff(grid[i][j], val);
				val++;
			}
		}
	}
	vector<unordered_set<int>> adj(val+1); 
	for(int i = 0; i < H; i++){
		for(int j = 0; j < W; j++){
			if(grid[i][j] != 0){
				for(auto [dx, dy] : dir){
					if(i+dx > -1 && i+dx < H && j+dy > -1 && j+dy < W && grid[i+dx][j+dy] != grid[i][j] && grid[i+dx][j+dy] != 0){
						adj[cc[i][j]].insert(cc[i+dx][j+dy]);
						adj[cc[i+dx][j+dy]].insert(cc[i][j]);
					}
				}
			}
		}
	}
	queue<int> q1;
	q1.push(0);
	vector<int> v(val+1, 0), d(val+1, 0);
	v[0] = 1;
	int ans = 0;
	while(!q1.empty()){
		auto temp = q1.front();
		q1.pop();
		for(auto i : adj[temp]){
			if(!v[i]){
				q1.push(i);
				v[i] = 1;
				d[i] = d[temp] + 1;
				ans = max(ans, d[i]);
			}
		}
	}
	cout<<ans+1<<endl;
	return 0;
}

Subtask #1

30.0 / 30.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	79 ms	135248 KB	Output is correct
2	Correct	46 ms	125524 KB	Output is correct
3	Correct	47 ms	125780 KB	Output is correct
4	Correct	60 ms	126548 KB	Output is correct
5	Correct	54 ms	127572 KB	Output is correct
6	Correct	45 ms	125524 KB	Output is correct
7	Correct	46 ms	125676 KB	Output is correct
8	Correct	48 ms	125776 KB	Output is correct
9	Correct	46 ms	125772 KB	Output is correct
10	Correct	51 ms	127636 KB	Output is correct
11	Correct	50 ms	125896 KB	Output is correct
12	Correct	62 ms	129132 KB	Output is correct
13	Correct	56 ms	127572 KB	Output is correct
14	Correct	50 ms	127572 KB	Output is correct
15	Correct	72 ms	135248 KB	Output is correct
16	Correct	96 ms	135340 KB	Output is correct
17	Correct	68 ms	134484 KB	Output is correct
18	Correct	54 ms	126636 KB	Output is correct

Subtask #2

65.625 / 70.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	49 ms	126804 KB	Output is correct
2	Correct	165 ms	175440 KB	Output is correct
3	Correct	985 ms	485204 KB	Output is correct
4	Correct	249 ms	189304 KB	Output is correct
5	Runtime error	1417 ms	1048576 KB	Execution killed with signal 9
6	Correct	1274 ms	272776 KB	Output is correct
7	Correct	49 ms	126664 KB	Output is correct
8	Correct	49 ms	126980 KB	Output is correct
9	Correct	50 ms	127312 KB	Output is correct
10	Correct	47 ms	126292 KB	Output is correct
11	Correct	48 ms	126184 KB	Output is correct
12	Correct	51 ms	128340 KB	Output is correct
13	Correct	177 ms	175324 KB	Output is correct
14	Correct	129 ms	154708 KB	Output is correct
15	Correct	154 ms	160060 KB	Output is correct
16	Correct	104 ms	148568 KB	Output is correct
17	Correct	391 ms	254800 KB	Output is correct
18	Correct	478 ms	258428 KB	Output is correct
19	Correct	305 ms	189268 KB	Output is correct
20	Correct	222 ms	207596 KB	Output is correct
21	Correct	481 ms	340308 KB	Output is correct
22	Runtime error	1453 ms	1048576 KB	Execution killed with signal 9
23	Correct	811 ms	374364 KB	Output is correct
24	Correct	791 ms	484084 KB	Output is correct
25	Correct	1787 ms	672848 KB	Output is correct
26	Correct	528 ms	131920 KB	Output is correct
27	Correct	673 ms	138260 KB	Output is correct
28	Correct	1227 ms	268860 KB	Output is correct
29	Correct	1110 ms	214768 KB	Output is correct
30	Correct	936 ms	190620 KB	Output is correct
31	Correct	1896 ms	516640 KB	Output is correct
32	Correct	677 ms	166320 KB	Output is correct