Cod sursa(job #1998668)

Utilizator Victor24Vasiesiu Victor Victor24 Data 8 iulie 2017 18:26:23
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.06 kb
#include <bits/stdc++.h>
#define pr first
#define ul second

using namespace std;

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

vector <int> v[100005];

queue < pair < int , int > > q;

int n, m, i, x, y, s, fv[100005];

pair <int, int> aux;

int main ()
{
    fin>>n>>m>>s;

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

    q.push( { s , 0 } );

    while (!q.empty())
    {
        aux = q.front();
        q.pop();

        for ( i = 0 ; i < v[aux.pr].size() ; i++ )
        {
            if ( fv[v[aux.pr][i]] == 0 )
            {
                fv[v[aux.pr][i]] = aux.ul + 1;
                q.push( {v[aux.pr][i], aux.ul+1} );
            }
        }

    }

    fv[s] = 0;

    for ( i = 1 ; i <= n ; i++ )
    {
        if ( i != s && fv[i] != 0 )
        {
            fout<<fv[i]<<" ";
        }
        else if ( i == s )
        {
            fout<<0<<" ";
        }
        else
        {
            fout<<-1<<" ";
        }
    }

    return 0;
}