Cod sursa(job #1479373)

Utilizator superstar1998Moldoveanu Vlad superstar1998 Data 31 august 2015 10:37:19
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.91 kb
#include <iostream>
#include <fstream>
using namespace std;
struct nod{int x;nod* urm;};
nod* L[1000001];
int n,m,s,q[100001],D[100001];
bool viz[100001];
void Citeste()
{
    ifstream f("bfs.in");
    f>>n>>m>>s;
    int x,y;
    for(int i=1;i<=m;i++)
    {
        f>>x>>y;
        nod* c = new nod;
        c->x=y;
        c->urm=L[x];
        L[x]=c;
    }
    f.close();
}
void BF(int x)
{
    int p,u;
    p=u=1;
    q[1]=x;
    viz[x]=true;
    while(p<=u)
    {
        for(nod* c=L[q[p]];c;c=c->urm)
            if(!viz[c->x])
            {
                q[++u]=c->x;
                viz[c->x]=true;
                D[c->x]=D[q[p]]+1;
            }
        p++;
    }
}
void Scrie()
{
    ofstream g("bfs.out");
    for(int i=1;i<=n;i++)
        if(D[i]==0&&i!=s) g<<"-1 ";
        else g<<D[i]<<" ";
}
int main()
{
    Citeste();
    BF(s);
    Scrie();
    return 0;
}