Cod sursa(job #2509524)

Utilizator andaraluca2001Anda Epure andaraluca2001 Data 14 decembrie 2019 12:25:49
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.79 kb
#include <fstream>

using namespace std;

const int N=100009;
const int M = 1000001;

int q[N],d[N],lst[N],vf[M],n,m,start,L,D,nr,urm[M];

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

void adauga(int x, int y)
{

    vf[++nr]=y;
    urm[nr]=lst[x];
    lst[x]=nr;

}


void bfs(int x0)
{
   int st,dr;
   for(int i=1;i<=n;i++) d[i]=-1;

   st=0;
   dr=-1;

   q[++dr]=x0;
   d[x0]=0;

   while(st<=dr)
   {
      int x=q[st++];
      for(int p=lst[x];p!=0;p=urm[p])
      {
          int y=vf[p];
          if(d[y]==-1)
          {
             q[++dr]=y;
             d[y]=1+d[x];
          }
      }
   }
}

int main()
{
    in>>n>>m>>start;

    for(int i=1;i<=m;i++)
    {
        in>>L>>D;
        adauga(L,D);

    }

    bfs(start);

    for(int i=1;i<=n;i++) out<<d[i]<<" ";

    return 0;
}