Cod sursa(job #984566)

Utilizator alex_HarryBabalau Alexandru alex_Harry Data 14 august 2013 19:56:31
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.9 kb
#include <fstream>
#include <vector>
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
int N,M,S;
int C[100002],Use[100002],D[100002];
vector <int> G[100002];
void Read()
{
    f>>N>>M>>S;
    int i;
    for(i=1;i<=M;i++)
    {
        int x,y;
        f>>x>>y;
        G[x].push_back(y);
    }
}
void BFS()
{
    int i;
    C[1]=S;Use[S]=1;
    int k=1;
    for(i=1;i<=k;i++)
    {
        int nod=C[i];
        for(unsigned int j=0;j<G[nod].size();j++)
            if(!Use[G[nod][j]])
            {
                C[++k]=G[nod][j];
                D[G[nod][j]]=D[nod]+1;
                Use[C[k]]=1;
            }
    }
}
void Print()
{
    int i;
    for(i=1;i<=N;i++)
    {
        if(Use[i])
            g<<D[i]<<" ";
        else
            g<<-1<<" ";
    }
    g<<"\n";
}
int main()
{
    Read();
    BFS();
    Print();
    return 0;
}