Cod sursa(job #2671595)

Utilizator sorinturdaSorin Turda sorinturda Data 12 noiembrie 2020 13:45:33
Problema BFS - Parcurgere in latime Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.77 kb
#include <bits/stdc++.h>

using namespace std;

ifstream in("bfs.in");
ofstream out("bfs.out");
const int NN=100001;

int n,m,s,v[NN],p[NN];
vector <int> a[NN];
queue <pair<int, int> > q;

void bfs(int nod, int x){
  q.push({nod,x});
  while(!q.empty()){
    int vf=q.front().first;
    int grd=q.front().second;
    q.pop();
    p[vf]=1;
    v[vf]=grd;
    for(int i=0;i<a[vf].size();i++){
      if(!p[a[vf][i]]){
        q.push({a[vf][i],grd+1});
      }
    }
  }
}

int main() {
  in>>n>>m>>s;
    int x,y;
  while(m--){
    in>>x>>y;
    a[x].push_back(y);
  }
  bfs(s,0);
  for(int i=1;i<=n;i++){
    if(i==s)
      out<<0<<' ';
    else
      if(!v[i])
        out<<-1<<' ';
      else
        out<<v[i]<<' ';
  }
  return 0;
}