Cod sursa(job #956386)

Utilizator gabrieligabrieli gabrieli Data 2 iunie 2013 23:46:49
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.71 kb
#include <algorithm>
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <queue>
#include <vector>
using namespace std;

int main()
{
	ifstream fin ("bfs.in");
	ofstream fout ("bfs.out");

	int N, m, S;
	fin >> N >> m >> S;
	vector <vector <int>> G (N+1);
	vector <int> dist (N+1, -1);

	for (; m; --m)
	{
		int x, y;
		fin >> x >> y;
		G[x].push_back (y);
	}

	queue <int> vertices;
	vertices.push (S);
	dist[S] = 0;
	
	while (!vertices.empty())
	{
		int v = vertices.front(); vertices.pop();
		for (auto &n : G[v])
			if (dist[n] == -1)
			{
				dist[n] = dist[v]+1;
				vertices.push (n);
			}
	}

	for (int v = 1; v <= N; ++v)
		fout << dist[v] << ' ';
	fout << '\n';

	fin.close();
	return EXIT_SUCCESS;
}