Cod sursa(job #2706883)

Utilizator razviOKPopan Razvan Calin razviOK Data 15 februarie 2021 22:50:04
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.93 kb
#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
vector<int> G[100001];
int N,M,x,y,S;
int Coada[100001],st=1,dr;
int viz[100001];
void BFS()
{
    while(st<=dr)
    {
        int nod_curent=Coada[st];
        st++;
        for(vector<int>::iterator nod=G[nod_curent].begin(); nod!=G[nod_curent].end(); ++nod)
            if(!viz[*nod] && *nod!=S)
            {
                viz[*nod]=viz[nod_curent]+1;
                Coada[++dr]=*nod;
            }

    }
}
int main()
{
    f>>N>>M>>S;
    for(int i=1; i<=M; i++)
    {
        f>>x>>y;
        G[x].push_back(y);
    }

    Coada[++dr]=S;
    BFS();


    for(int i=1; i<=N; i++)
    {
        if(i==S)
            g<<0<<" ";
        else
        {
            if(!viz[i])
                g<<-1<<" ";
            else g<<viz[i]<<" ";
        }
    }
    return 0;
}