Cod sursa(job #1180080)

Utilizator Aavatar36Russu Vadim Aavatar36 Data 29 aprilie 2014 21:53:29
Problema BFS - Parcurgere in latime Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 1.48 kb
#include <queue>
#include <vector>
#include <fstream>
using namespace std;

int n, m, s;
vector<int> v[100002];
queue<int> coada;
int a[100002];
bool p[100002];

int bfs(int nod)
{
    for (int i = 0; i < v[nod].size(); ++i)
    {
        if (!p[v[nod][i]])
        {
            a[v[nod][i]] = a[nod] + 1;
            p[v[nod][i]] = 1;
            bfs(v[nod][i]);
        }
    }

}

int main()
{
    ifstream fin("bfs.in");

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

    a[s] = 0;
    p[s] = 1;
    //  int nod;
    /* coada.push(s);
     while (!coada.empty())
     {
         nod = coada.front();
     //    fout << nod << " ";
         for (int i = 0; i < v[nod].size(); ++i)
         {
             if (!p[v[nod][i]])
             {
                 a[v[nod][i]] = a[nod] + 1;
                 p[v[nod][i]] = 1;
                 coada.push(v[nod][i]);
             }
         }
         coada.pop();
     }*/
    //   fout << "\n\n";
    bfs(s);
    ofstream fout("bfs.out");
    for (int i = 1; i <= n ; ++i)
    {
        if (!p[i])
        {
            fout << "-1 ";
        }
        else
            fout << a[i] << " ";
    }

}













/* for (int i = 1; i <= n; ++i)
 {
     fout << i << " ";
     for (int j = 0; j < v[i].size(); ++j)
     {
         fout << v[i][j] << " ";
     }
     fout << "\n";
 }*/