Cod sursa(job #2215184)

Utilizator Anastasia11Susciuc Anastasia Anastasia11 Data 21 iunie 2018 11:33:49
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.87 kb
#include <fstream>
#include <vector>
#include <queue>
#define Nmax 100005

using namespace std;

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

int n, m, s;
int d[Nmax];
vector <int> v[Nmax];
queue <int> Q;
bool seen[Nmax];

int main()
{
    f >> n >> m >> s;
    int x, y;
    while(m -- )
    {
        f >> x >> y;
        v[x].push_back(y);
    }
    Q.push(s);seen[s]=1;d[s]=1;
    while(!Q.empty())
    {
        int node=Q.front();
        Q.pop();
        for ( int i = 0, l=v[node].size(); i < l; i ++ )
        {
            int nnode=v[node][i];
            if(seen[nnode] == 1) continue;
            d[nnode]=d[nnode]+d[node]+1;
            seen[nnode]=1;
            Q.push(nnode);
        }
    }
    for ( int i = 1; i <= n; i ++ )
        if(d[i] == 0)
        g << "-1 ";
    else
        g << d[i]-1 << " ";

    return 0;
}