Cod sursa(job #1509454)

Utilizator VladuZ1338Vlad Vlad VladuZ1338 Data 23 octombrie 2015 22:03:02
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.7 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

const int Nmax = 100001;
vector <int> v[Nmax];
vector <int> ::iterator it;
queue <int> Q;
int n, m, s, i, x, y, viz[Nmax], xc;

void BFS (int xi)
{
	Q.push (xi); viz[xi]=1;
	while (!Q.empty())
	{
		xc=Q.front(); Q.pop();
		for (it=v[xc].begin(); it!=v[xc].end(); it++)
		{
			if (viz[*it]==0)
			{
				viz[*it]=viz[xc]+1;
				Q.push (*it);
			}
		}
	}
}

int main()
{
	fin >> n >> m >> s;
	for (i=1; i<=m; i++)
	{
		fin >> x >> y;
		v[x].push_back(y);
	}
	BFS (s);
	for (i=1; i<=n; i++)
	{
		fout << viz[i]-1 << " ";
	}
}