Cod sursa(job #2130203)

Utilizator StepHoria Stefan Step Data 13 februarie 2018 15:32:31
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.74 kb
#include <iostream>
#include <vector>
#include <fstream>

using namespace std;

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

const int N=100001;
int m,n,q[N],d[N],st,dr=-1,s;

vector <int> a[N];

void citire ()
{
    int x,y;
    f>>n>>m>>s;
    for (int i=1;i<m;i++)
    {
        f>>x>>y;
        a[x].push_back(y);
    }
}

int main()
{
    int x,y;
    citire();
    for (int i=0;i<=n;i++)
        d[i]=-1;
    //bfs;

    q[++dr]=s;
    d[s]=0;
    while (st<=dr)
    {
        x=q[st++];
        for (int i=0;i<a[x].size();i++)
        {
            y=a[x][i];
            if (d[y]==-1)
            {
                q[++dr]=y;
                d[y]=1+d[x];
            }
        }
    }
    for (int i=1;i<=n;i++)
        g<<d[i]<<" ";
    return 0;
}