Cod sursa(job #2222513)

Utilizator strutu_iStrutu Ilinca Ioana strutu_i Data 17 iulie 2018 10:39:01
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.88 kb
#include <fstream>
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
const int NMAX=100000;
vector <int> viz,d;
vector <int> G[NMAX+5];
vector <int>::iterator it;
void bfs(int u, int cc)
{
  queue <int> q; int v;
  q.push(u);viz[u]=cc;
  while(!q.empty())
  {
    u=q.front();q.pop();
    for(it=G[u].begin();it!=G[u].end();it++)
    {
      v=*it;
      if(!viz[v])
      {
        viz[v]=cc;d[v]=d[u]+1;
        q.push(v);
      }
    }
  }
}
int main()
{
    int n,m,i,u,v,cc=1,s;
    fin>>n>>m>>s;
    for(i=1;i<=m;i++)
    {
      fin>>u>>v;
      G[u].push_back(v);
    }
    viz.assign(n+1,0);
    d.assign(n+1,0);
    bfs(s,cc);
    for(i=1;i<=n;i++)
    {
      if(viz[i]!=cc)
         fout<<-1<<" ";
      else
         fout<<d[i]<<" ";
    }
    return 0;
}