Cod sursa(job #799632)

Utilizator ard_procesoareLupicu ard_procesoare Data 19 octombrie 2012 17:23:29
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.94 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

const int N = 100001;

ifstream fin("bfs.in");
ofstream fout("bfs.out");
vector <int>  a[N];
queue <int> q;
int n,m,d[N],g,x,y;
void citire()
{
    fin>>n>>m>>g;
    for(int i=0;i<m;i++)
    {
        fin>>x>>y;
        a[x].push_back(y);
    }
    for(int i=0;i<=n;i++)
        d[i]=-1;
}
void bfs()
{
        q.push(g);
        d[g]=0;
        while(!q.empty())
        {
            x=q.front();
            q.pop();
            for(size_t i=0;i<a[x].size();i++)
            {
                y=a[x][i];
                if(d[y]==-1)
                {
                    q.push(y);
                    d[y]=1+d[x];

                }
            }
        }
}
void tipar()
{
    int i=n;
    for(i=1;i<=n;i++)
    {
            fout<<d[i]<<" ";
    }
}
int main()
{
   citire();
   bfs();
   tipar();
}