Cod sursa(job #1345032)

Utilizator DragodanAlexandraDragodan Alexandra DragodanAlexandra Data 17 februarie 2015 10:37:16
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.9 kb
#include <iostream>
#include<vector>
#include<fstream>
#include<limits>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");

vector<vector<int> > a;
int n,s,viz[100001],c[100001],w[100001];

void bfs(int i)
{
    int u,p,v;
    c[1]=i;
    viz[i]=1;
    w[i]=0;
    u=p=1;
    while(p<=u)
    {
        v=c[p++];
        for(vector<int>::iterator it=a[v].begin();it!=a[v].end();it++)
        if(viz[*it]==0)
        {
            c[++u]=*it;
            viz[*it]=1;
            w[*it]=w[v]+1;
        }

    }
}

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

void afisare()
{
    int i;
    for(i=1;i<=n;i++) g<<w[i]<<" ";
}

int main()
{
    citire();
    bfs(s);
    afisare();

    return 0;
}