Cod sursa(job #2662570)

Utilizator Guccifer2429Julien Iancu Guccifer2429 Data 24 octombrie 2020 11:28:29
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.05 kb
#include    <iostream>
#include    <fstream>
#include    <vector>
#include    <queue>

using namespace std;

ifstream fin("bfs.in");
ofstream fout("bfs.out");

const int NLIM = 100005;

int N, M, S;
int Distance[NLIM];

vector <int> Edge[NLIM];
queue <int> Q;

void BFS()
{
    int Node, Next;
    while(!Q.empty())
    {
        Node =  Q.front();
        Q.pop();
        for(unsigned int i = 0; i < Edge[Node].size(); i++)
        {
            Next = Edge[Node][i];
            if(Distance[Next] == -1)
            {
                Q.push(Next);
                Distance[Next] = Distance[Node] + 1;
            }
        }
    }
}

void Read()
{
    fin >> N >> M >> S;
    for(int i = 1; i <= M; i++)
    {
        int x, y;
        fin >> x >> y;
        Edge[x].push_back(y);
    }
    for(int i = 1; i <= N; i++)
        Distance[i] = -1;
    Distance[S] = 0;

    Q.push(S);

    BFS();

    for(int i = 1; i <= N; i++)
        fout << Distance[i] << " ";
}

int main()
{
    Read();
    return 0;
}