Cod sursa(job #1838397)

Utilizator SagunistuStrimbu Alexandru Sagunistu Data 31 decembrie 2016 21:37:02
Problema BFS - Parcurgere in latime Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.92 kb
#include <fstream>
#include <queue>
#include <vector>
#define nmax 100005

using namespace std;

int n,m,s,d[nmax];
bool viz[nmax];
vector <int> g[nmax];
queue <int> q;

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

void citire()
{
    int x,y;
    fin>>n>>m>>s;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y;
        g[x].push_back(y);
    }
    for(int i=1;i<=n;i++)
        d[i]=-1;
}

void bfs()
{
    q.push(s);
    d[s]=0;
    while(!q.empty())
    {
        int k = q.front();
        viz[k]=1;
        q.pop();
        for(vector<int>::iterator ii=g[k].begin();ii!=g[k].end();++ii)
            if(!viz[*ii])
            {
                d[*ii] = d[k] + 1;
                q.push(*ii);
            }

    }
}

void afisare()
{
    for(int i=1;i<=n;i++)
        fout<<d[i]<<" ";
    fout<<"\n";
}

int main()
{
    citire();
    bfs();
    afisare();
    return 0;
}