Cod sursa(job #1293796)

Utilizator stefanlaculeanuLaculeanu Stefan stefanlaculeanu Data 16 decembrie 2014 16:25:26
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.86 kb
#include <iostream>
#include <fstream>
using namespace std;

ifstream in("bfs.in");
ofstream out("bfs.out");

int n, m , s ,nr , lst[100001],vf[1000001],urm[1000001] , INF = -1 ,q[1000001] , d[1000001] ;

void adauga(int x , int y)
{
    vf[++nr]=y;
    urm[nr]=lst[x];
    lst[x]=nr;
}

void bfs( int x)
{
    int p=1,u=0,poz,y;
    q[++u]=x;
    d[x]=0;
    while(p<=u)
    {
        x=q[p++];
        poz=lst[x];
        while(poz!=0)
        {
            y=vf[poz];
            if(d[y]==INF)
            {
                d[y]=1+d[x];
                q[++u]=y;
            }
            poz=urm[poz];
        }
    }
}

int main()
{
    int i , x , y;
    in>>n>>m>>s;
    for(i=1; i<=m; i++)
    {
        in>>x>>y;
        adauga(x,y);
    }

    for(i=1; i<=n; i++)
        d[i]=-1;
    bfs(s);
    for(i=1; i<=n; i++)
    {
        out<<d[i]<<" ";
    }
    return 0;
}