Cod sursa(job #988214)

Utilizator rares96cheseliRares Cheseli rares96cheseli Data 22 august 2013 12:22:35
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.8 kb
#include <fstream>
#include <deque>
#include <vector>
#include <cstring>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");

vector < int > G[100005];
int n, m, cost[100005], s;
deque < int > Q;

void bfs(int sursa)
{
    memset(cost, -1, sizeof(cost));
    Q.push_back(sursa);
    cost[sursa]=0;
    while (Q.size())
    {
        int nod=Q.front(); Q.pop_front();
        for (int i=0; i<G[nod].size(); ++i)
            if (cost[G[nod][i]]==-1)
            {
                cost[G[nod][i]]=cost[nod]+1;
                Q.push_back(G[nod][i]);
            }
    }
}

int main()
{
    f>>n>>m>>s;
    for (int i=1; i<=m; ++i)
    {
        int x, y; f>>x>>y;
        G[x].push_back(y);
    }
    bfs(s);
    for (int i=1; i<=n; ++i) g<<cost[i]<<' ';
    return 0;
}