Cod sursa(job #662397)

Utilizator valentina506Moraru Valentina valentina506 Data 16 ianuarie 2012 17:35:41
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.71 kb
#include<fstream>
#include<algorithm>
#include<queue>
#define inf 1<<30
using namespace std;
int n,m,start,i,j,x,y,c;
vector<int> a[100001];
vector<int> d(100001,inf);
queue<int>q;

void bf(int x)
{
	int i;
	q.push(x);
	while(!q.empty())
	{
		x=q.front();
		q.pop();
		for(i=0;i<a[x].size();++i)
			if(d[a[x][i]]>d[x]+1)
			{
				d[a[x][i]]=d[x]+1;
				q.push(a[x][i]);
			}
	}
}

int main()
{
	freopen("bfs.in","r",stdin);
	freopen("bfs.out","w",stdout);
	scanf("%d%d%d",&n,&m,&start);
	
	for(i=1;i<=m;++i)
	{
		scanf("%d%d",&x,&y);
		a[x].push_back(y);
	}
	d[start]=0;
	bf(start);
	
	for(i=1;i<=n;++i)
		if(d[i]!=inf)
			printf("%d ",d[i]);
		else
			printf("-1 ");
		return 0;
}