Cod sursa(job #631826)

Utilizator tomaAndrei Toma toma Data 9 noiembrie 2011 20:25:53
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.66 kb
#include<stdio.h>
#include<string.h>
#include<vector>
using namespace std;
int sol[100001],S;
vector<int> a[100001],Q;
vector<int>::iterator it;
void BF()
{
	int i;
	memset(sol,-1,sizeof(sol));
	Q.push_back(S);
	sol[S]=0;
	i=0;
	while (i!=Q.size())
	{
		for (it=a[Q[i]].begin();it!=a[Q[i]].end();++it)
			if (sol[*it]==-1)
			{
				Q.push_back(*it);
				sol[*it]=sol[Q[i]]+1;
			}
		++i;
	}
}
int main()
{
	int N,M,i,x,y;
	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);
	}
	BF();
	for (i=1;i<=N;++i)
		printf("%d ",sol[i]);
}