Cod sursa(job #782083)

Utilizator RaduDoStochitoiu Radu RaduDo Data 25 august 2012 20:20:46
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.74 kb
#include<iostream>
#include<cstring>
#include<cstdio>
#include<vector>
using namespace std;
#define maxn 100005


vector <int> a[maxn];
int g[maxn],cost[maxn],l[maxn],nr[maxn],i,j,n,m,s,p,x,y;

void bfs(int nod)
{
	memset(cost,-1,sizeof(cost));
	cost[nod]=0;
	p=1;
	l[p]=nod;

	for(i=1;i<=p;++i)
		for(j=0;j<g[l[i]];++j)
			if(cost[a[l[i]][j]] == -1)
			{
				l[++p]=a[l[i]][j];
				cost[l[p]]=cost[l[i]]+1;
			}	
}

int main()
{
	freopen("bfs.in","r",stdin);
	freopen("bfs.out","w",stdout);
	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)
		g[i]=a[i].size();
	bfs(s);
	for(i=1;i<=n;++i)
		printf("%d ",cost[i]);
	
	printf("\n");
	return 0;
}