Cod sursa(job #2229326)

Utilizator vladsirbu23Vlad Sirbu vladsirbu23 Data 6 august 2018 16:07:50
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.03 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
int N,M,Start[100010],T[2][2000010],rez[100010],q[100010],viz[100010];
void init()
{
    int i;
    for(i=1;i<=N;i++)
    {
        rez[i]=-1;
    }
}
void citire()
{
    int i,x,y;
    for(i=1;i<=M;i++)
    {
        fin>>x>>y;
        T[0][i]=y;
        T[1][i]=Start[x];
        Start[x]=i;
    }
}
void bfs(int S)
{
    int ci,cs,k,p;
    ci=1;
    cs=1;
    rez[S]=0;
    viz[S]=1;
    q[cs]=S;
    while(cs<=ci)
    {
       p=Start[q[cs]];
       while(p!=0)
       {
           if(viz[T[0][p]]==0)
           {
           ci++;
           q[ci]=T[0][p];
           rez[q[ci]]=rez[q[cs]]+1;
           viz[q[ci]]=1;
           }
           p=T[1][p];
       }
       cs++;
    }
}
void afisare()
{
    int i;
    for(i=1;i<=N;i++)
    {
        fout<<rez[i]<<" ";
    }
}
int main()
{
    int S,i,p;
    fin>>N>>M>>S;
    init();
    citire();
    bfs(S);
    afisare();
}