Cod sursa(job #923462)

Utilizator StefansebiStefan Sebastian Stefansebi Data 23 martie 2013 17:15:14
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.04 kb
#include<fstream>
#include<queue>
#include<list>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");
int n, m, cost[100005], s;
queue <int> q;
list <int> vecini[100005];

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

void setcost() {
    int i;
    for (i = 1; i <= n; i++)
        cost[i] = -1;

}

void afiscost() {
    int i;
    for (i = 1; i <= n; i++)
        fout << cost[i] << " ";

}

int bfs(int start) {
    int x, y, i;
    cost[start] = 0;
    q.push(start);
    while (!q.empty()) {
           x = q.front();
           q.pop();
           while (!vecini[x].empty()){
               y = vecini[x].front();
               vecini[x].pop_front();
               if (cost[y] == -1) {
                   cost[y] = cost[x] + 1;
                   q.push(y);
               }
           }
    }
}

int main() {
    citire();
    setcost();
    bfs(s);
    afiscost();
}