Cod sursa(job #505820)

Utilizator andu04Popa Andi andu04 Data 4 decembrie 2010 10:22:14
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.04 kb
#include <iostream>
#include <stdio.h>
#define LGMAX 100001
using namespace std;

int n,m,s;

struct nod{
    int inf;
    nod *urm;
};
nod *g[100001];

void add(int x,int y)
{
    nod *aux=new nod;
    aux->inf=y;
    aux->urm=g[x];
    g[x]=aux;
}
void citire()
{
    freopen ("bfs.in","r",stdin);
    scanf ("%d%d%d",&n,&m,&s);
    int x,y;
    for (int i=0;i<m;i++)
    {
        scanf ("%d%d",&x,&y);
        add(x,y);
    }
}
int st[LGMAX],viz[LGMAX],sf,lg[LGMAX];
void bfs(int x)
{
    viz[x]=1;lg[x]=0;
    st[0]=x;
    sf=1;
    for (int i=0;i<sf;i++)
        for (nod *p=g[st[i]];p;p=p->urm)
            if (!viz[p->inf])
            {
                viz[p->inf]=1;
                st[sf++]=p->inf;
                lg[p->inf]=lg[st[i]]+1;
            }
}
void afis()
{
    freopen ("bfs.out","w",stdout);
    citire();
    bfs(s);
    for (int i=1;i<=n;i++)
    {
        if (!lg[i] && i!=s)
            lg[i]=-1;
        printf ("%d ",lg[i]);
    }
}
int main()
{
    afis();
    return 0;
}