Cod sursa(job #525837)

Utilizator DraStiKDragos Oprica DraStiK Data 26 ianuarie 2011 15:22:23
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.98 kb
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;

#define pb push_back
#define DIM 100005

vector <int> g[DIM];
queue <int> q;
int dst[DIM];
int n,m,s;

void read ()
{
    int i,x,y;

    scanf ("%d%d%d",&n,&m,&s);
    for (i=1; i<=m; ++i)
    {
        scanf ("%d%d",&x,&y);
        g[x].pb (y);
    }
}

void solve ()
{
    vector <int> :: iterator it;
    int nod;

    memset (dst,-1,sizeof (dst));
    dst[s]=0;
    for (q.push (s); !q.empty (); q.pop ())
    {
        nod=q.front ();
        for (it=g[nod].begin (); it!=g[nod].end (); ++it)
            if (dst[*it]<0)
            {
                dst[*it]=dst[nod]+1;
                q.push (*it);
            }

    }
}

void print ()
{
    int i;

    for (i=1; i<=n; ++i)
        printf ("%d ",dst[i]);
}

int main ()
{
    freopen ("bfs.in","r",stdin);
    freopen ("bfs.out","w",stdout);

    read ();
    solve ();
    print ();

    return 0;
}