Cod sursa(job #315387)

Utilizator moonbeamElma Moonbeam moonbeam Data 15 mai 2009 12:19:19
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.81 kb
#include<stdio.h>
#define N 100005
#define M 1000005
int *a[N],x[M],y[M],n,m,s,d[N],v[M];
void bfs(int s)
{
	int coada[N],x,y,u,p;
	u=p=0;
	for (int i=1; i<=n; ++i)
		d[i]=-1;
	coada[u++]=s;
	v[s]=1;
	d[s]=0;
	while (u!=p)
	{
		x=coada[p++];
		for (int i=1; i<=a[x][0]; ++i)
		{
			y=a[x][i];
			if (!v[y])
			{
				coada[u++]=y;
				d[y]=1+d[x];
				v[y]=1;
			}
		}
	}
	for (int i=1; i<=n; ++i)
		printf("%d ",d[i]);
}
void citire()
{
	freopen("bfs.in","r",stdin);
	freopen("bfs.out","w",stdout);
	scanf("%d%d%d",&n,&m,&s);
	for (int i=1; i<=m; ++i)
	{
		scanf("%d%d",&x[i],&y[i]);
		++d[x[i]];
	}
	for (int i=1; i<=n; ++i)
	{
		a[i]=new int [1+d[i]];
		a[i][0]=0;
	}
	for (int i=1; i<=m; ++i)
		a[x[i]][++a[x[i]][0]]=y[i];
	bfs(s);
}
int main()
{
	citire();
	return 0;
}