oj.uz

Submission #69486

# Submission time Handle Problem Language Result Execution time Memory
69486 2018-08-21T03:11:56 Z MatheusLealV Tracks in the Snow (BOI13_tracks) C++17
75.9375 / 100
 2000 ms 694600 KB 
#include <bits/stdc++.h>
#define N 4001
#define f first
#define s second
using namespace std;
typedef pair<int, int> pii;

int n, m, ans, cnt, dx[4] = {0, 0, 1, -1}, dy[4] = {1, -1, 0, 0};

int id[N][N], pai[N*N], dist[N*N];

bool ok[N][N];

char mat[N][N], T;

vector<int> grafo[N*N];

inline void bfs(int x, int y, int &p)
{
	queue< pii > fila;

	fila.push({x, y});

	while(!fila.empty())
	{
		int x = fila.front().f, y = fila.front().s;

		fila.pop();

		ok[x][y] = 1;

		pai[id[x][y]] = p;

		for(int pp = 0; pp < 4; pp++)
		{
			int a = x + dx[pp], b = y + dy[pp];

			if(!a or !b or a > n or b > m or mat[a][b] != mat[x][y] or ok[a][b]) continue;

			ok[a][b] = 1;

			fila.push({a, b});
		}
	}
}

int main()
{
	ios::sync_with_stdio(false); cin.tie(0);

	cin>>n>>m;

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

		 	id[i][j] = ++cnt;

		 	pai[id[i][j]] = id[i][j];
		}
	}

	for(int i = 1; i <= n; i++)
	{
		for(int j = 1; j <= m; j++)
		{
			if(mat[i][j] == '.' or ok[i][j]) continue;

			bfs(i, j, id[i][j]);	
		}
	}

	for(int i = 1; i <= n; i++)
	{
		for(int j = 1; j <= m; j++)
		{
			if(mat[i][j] == '.') continue;

			for(int p = 0; p < 4; p++)
			{
				int a = i + dx[p], b = j + dy[p];

				if(!a or !b or a > n or b > m) continue;

				if(mat[a][b] != mat[i][j] and mat[a][b] != '.')
				{
					int u = pai[id[a][b]], v = pai[id[i][j]];

					grafo[v].push_back(u);
				}
			}
		}
	}

	queue<int> fila;

	dist[pai[id[1][1]]] = 1;

	fila.push(pai[id[1][1]]);

	while(!fila.empty())
	{
		int x = fila.front();

		ans = max(ans, dist[x]);

		fila.pop();

		for(auto v: grafo[x])
		{
			if(dist[v] == 0)
			{
				dist[v] = dist[x] + 1;

				fila.push(v);
			}
		}
	}

	cout<<ans<<"\n";
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 385 ms 388048 KB Output is correct
2 Correct 348 ms 388048 KB Output is correct
3 Correct 337 ms 388048 KB Output is correct
4 Correct 385 ms 388048 KB Output is correct
5 Correct 354 ms 388048 KB Output is correct
6 Correct 391 ms 388048 KB Output is correct
7 Correct 367 ms 388048 KB Output is correct
8 Correct 376 ms 388048 KB Output is correct
9 Correct 344 ms 388048 KB Output is correct
10 Correct 407 ms 388048 KB Output is correct
11 Correct 362 ms 388048 KB Output is correct
12 Correct 367 ms 388048 KB Output is correct
13 Correct 353 ms 388048 KB Output is correct
14 Correct 353 ms 388048 KB Output is correct
15 Correct 420 ms 388928 KB Output is correct
16 Correct 474 ms 389640 KB Output is correct
17 Correct 387 ms 389640 KB Output is correct
18 Correct 368 ms 389640 KB Output is correct

Subtask #2
45.9375 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 376 ms 424304 KB Output is correct
2 Correct 631 ms 424304 KB Output is correct
3 Correct 1597 ms 636216 KB Output is correct
4 Correct 673 ms 636216 KB Output is correct
5 Execution timed out 2105 ms 657028 KB Time limit exceeded
6 Execution timed out 2126 ms 657028 KB Time limit exceeded
7 Correct 390 ms 657028 KB Output is correct
8 Correct 472 ms 657028 KB Output is correct
9 Correct 397 ms 657028 KB Output is correct
10 Correct 344 ms 657028 KB Output is correct
11 Correct 446 ms 657028 KB Output is correct
12 Correct 396 ms 657028 KB Output is correct
13 Correct 602 ms 657028 KB Output is correct
14 Correct 462 ms 657028 KB Output is correct
15 Correct 569 ms 657028 KB Output is correct
16 Correct 431 ms 657028 KB Output is correct
17 Correct 892 ms 657028 KB Output is correct
18 Correct 1025 ms 657028 KB Output is correct
19 Correct 769 ms 657028 KB Output is correct
20 Correct 675 ms 657028 KB Output is correct
21 Correct 1099 ms 657028 KB Output is correct
22 Execution timed out 2092 ms 694600 KB Time limit exceeded
23 Correct 1328 ms 694600 KB Output is correct
24 Correct 1183 ms 694600 KB Output is correct
25 Execution timed out 2086 ms 694600 KB Time limit exceeded
26 Execution timed out 2082 ms 694600 KB Time limit exceeded
27 Execution timed out 2080 ms 694600 KB Time limit exceeded
28 Execution timed out 2115 ms 694600 KB Time limit exceeded
29 Execution timed out 2124 ms 694600 KB Time limit exceeded
30 Execution timed out 2095 ms 694600 KB Time limit exceeded
31 Execution timed out 2093 ms 694600 KB Time limit exceeded
32 Execution timed out 2114 ms 694600 KB Time limit exceeded