Cod sursa(job #2174189)

Utilizator george.ursachiUrsachi George george.ursachi Data 16 martie 2018 11:08:39
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.98 kb
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");

int N,M,cost[100005],S;
bool viz[100005];
vector <int> v[100005];
queue <int> c;
vector <int>::iterator it;

int BFS(int nodInitial)
{
    int nod,nod_nou;
    for(int i=1;i<=N;i++)
        cost[i]=-1;
    cost[nodInitial]=0;
    c.push(nodInitial);
    while(c.size())
    {
        nod=c.front();
        viz[nod]=1;
        for(it=v[nod].begin();it!=v[nod].end();it++)
        {
            nod_nou=*it;
            if(!viz[nod_nou] && cost[nod_nou]==-1)
            {
                c.push(nod_nou);
                cost[nod_nou]=cost[nod]+1;
            }
        }
        c.pop();
    }
}

int main()
{
    fin>>N>>M>>S;
    for(int i=1;i<=M;i++)
    {
        int x,y;
        fin>>x>>y;
        v[x].push_back(y);
    }
    BFS(S);
    for(int i=1;i<=N;i++)
    {
        fout<<cost[i]<<' ';
    }
    return 0;
}