Cod sursa(job #705987)

Utilizator valiro21Valentin Rosca valiro21 Data 5 martie 2012 12:01:16
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.87 kb
#include <cstdio>
#include <list>
#include <queue>
#define NMax 100001

using namespace std;

typedef queue<long> qc;
typedef list<long>::iterator it;

list<long> li[NMax];
long k,n,m,i,x,y,ii,pas,S;
long viz[NMax];

void dfs(long i)
{
	qc coada;
	coada.push(i);
	viz[i]=1;
	
	while(!coada.empty())
	{
		ii=coada.front();
		pas=viz[ii];
		
		for(it i=li[ii].begin();i!=li[ii].end();i++)
			if(pas+1<viz[*i]||viz[*i]==0)
			{
				coada.push(*i);
				viz[*i]=pas+1;
			}
		
		coada.pop();
	}
}

int main()
{
	freopen("bfs.in","rt",stdin);
	freopen("bfs.out","wt",stdout);
	
	scanf("%ld %ld %ld",&n,&m,&S);
	
	for(long i=1;i<=m;i++)
	{
		scanf("%ld %ld",&x,&y);
		li[x].push_back(y);
	}
	
	dfs(S);
	
	for(long i=1;i<=n;i++)
	{
		if(viz[i]==0)
			printf("-1 ");
		else
			printf("%ld ",viz[i]-1);
	}
	
	printf("\n");
	return 0;
}