Cod sursa(job #2130234)

Utilizator dariaana1504Corpaci Daria dariaana1504 Data 13 februarie 2018 15:54:00
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.74 kb
#include <fstream>
#include<vector>

using namespace std;

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

const int N=100001;

vector <int> a[N];

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

void citire()
{
    f>>n>>m>>s;
    for(int i=0; i<m; i++)
    {
        f>>x>>y;
        a[x].push_back(y);
    }
    for(int i=1; i<=n; i++)
    {
        d[i]=-1;
    }
}
void 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]<<" ";

    }
}

int main()
{
    citire();
    bfs();
    return 0;
}