Cod sursa(job #705053)

Utilizator andreinsAndrei Nae andreins Data 3 martie 2012 00:05:33
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.67 kb
#include<cstdio>
#include<vector>
#include<queue>
using namespace std;

vector<int> a[100100];
int d[100100];
queue<int> q;

void lee(int s, int n)
{
	int x,y;
	q.push(s);
	for(int i=1;i<=n;i++)
		d[i]=-1;
	d[s]=0;
	while(!q.empty())
	{
		x=q.front();
		q.pop();
		for(int i=0;i<=a[x].size();i++)
		{
			y=a[x][i];
			if(d[y]==-1)
			{
				q.push(y);
				d[y]=1+d[x];
			}
		}
	}
}

int main()
{
	int n,m,s,x,y;
	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,&y);
		a[x].push_back(y);
	}
	lee(s,n);
	for(int i=1;i<=n;i++)
		printf("%d ",d[i]);
	return 0;
}