Cod sursa(job #2518299)

Utilizator i.uniodCaramida Iustina-Andreea i.uniod Data 5 ianuarie 2020 14:52:51
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.96 kb
#include <fstream>
#include <vector>
#include <queue>
#define NMAX 100000 + 5
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");

int n, m, start;
vector <int> arce[NMAX];
queue <int> q;
int dist[NMAX];

void BFS(int s)
{
    dist[s] = 0;
    q.push(s);

    int nod, vecin;

    while(!q.empty())
    {
        nod = q.front();

        for(int i = 0; i < arce[nod].size(); ++ i)
        {
            vecin = arce[nod][i];
            if(dist[vecin] == -1)
            {
                q.push(vecin);
                dist[vecin] = dist[nod] + 1;
            }
        }

        q.pop();
    }
}

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

    for(int i = 1; i <= n; ++ i)
        dist[i] = -1;

    BFS(start);

    for(int i = 1; i <= n; ++ i)
        fout << dist[i] << " ";

    return 0;
}