Cod sursa(job #2671323)

Utilizator QubeeStefan Ste Qubee Data 11 noiembrie 2020 22:04:01
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.01 kb
#include <fstream>
#include <queue>
#include <vector>

using namespace std;

ifstream f("bfs.in");
ofstream g("bfs.out");

vector<int> graf[100001];

int n,m,start;
int distanta[100001];


void citire(){
    int x, y;

    f>>n>>m>>start;

    for(int i=1;i<=m;i++){
        f>>x>>y;
        graf[x].push_back(y);

    }

}



void BFS(int x){
    queue <int> coada;
    int nod;

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

    coada.push(x);

    distanta[x]=0;

    while(!coada.empty()) {

        nod=coada.front();

        coada.pop();

        for(int i=0; i < graf[nod].size(); i++)

            if(distanta[graf[nod][i]] == -1)
                {
                coada.push(graf[nod][i]);
                    distanta[graf[nod][i]] = distanta[nod] + 1;

            }

    }

}

void afisare(){

    for(int i=1;i<=n;i++)

        g<<distanta[i]<<" ";

}



int main(){

    citire();

    BFS(start);

    afisare();

    return 0;

}