Cod sursa(job #395675)

Utilizator taseTanase Alexandru tase Data 13 februarie 2010 17:00:42
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.63 kb
#include<stdio.h>
#include <vector>

using namespace std;

#define N 1<<17
int n,m,s,d[N],coada[N];
vector<int> a[N];
void bfs()
{
	int p,u,x,y,i;
	d[s]=0;
	p=u=0;
	coada[u++]=s;
	while(p!=u)
	{
		x=coada[p++];
		for(i=0;i<a[x].size();++i)
		{
			y=a[x][i];
			if(d[y]==-1)
			{
				d[y]=d[x]+1;
				coada[u++]=y;
			}
		}
	}
}
int main()
{
	freopen("bfs.in","r",stdin);
	freopen("bfs.out","w",stdout);
	int i,x,y;
	scanf("%d%d%d", &n,&m,&s);
	for(i=1;i<=m;++i)
	{
		scanf("%d%d",&x,&y);
		a[x].push_back(y);
	}
	for(i=1;i<=n;++i)
		d[i]=-1;
	bfs();
	for(i=1;i<=n;++i)
		printf("%d ",d[i]);
	return 0;
}