Cod sursa(job #1447901)

Utilizator andreator11ilies andreea andreator11 Data 5 iunie 2015 18:24:50
Problema BFS - Parcurgere in latime Scor 80
Compilator cpp Status done
Runda Arhiva educationala Marime 0.64 kb
#include <fstream>
#include <queue>
#include <set>

using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");

queue<int> q;
int n,m,s,fr[100001],i,a,b;
set<int> v[100001];
set<int>::iterator it;

int main()
{
    f>>n>>m>>s;
    for(i=1;i<=m;i++)
    {
        f>>a>>b;
        v[a].insert(b);
    }
    for(i=1;i<=n;i++)
      fr[i]=-1;
    q.push(s); fr[s]=0;
    while(!q.empty())
    {
     a=q.front();
     for (it=v[a].begin(); it!=v[a].end(); it++)
      if(fr[*it]==-1)
      {q.push(*it);
       fr[*it]=fr[a]+1;}
       q.pop();
    }
     for (i=1;i<=n;i++)
      g<<fr[i]<<" ";
    return 0;
}