Cod sursa(job #1492752)

Utilizator SmitOanea Smit Andrei Smit Data 28 septembrie 2015 09:31:04
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1 kb
#include <vector>
#include <fstream>

using namespace std;

int n,m,s,sol[100003],q[1000005],b[100003];
vector<int> a[100003];

inline void Citire()
{
    int i,x,y;
    ifstream fin("bfs.in");
    fin>>n>>m>>s;
    for(i=1;i<=m;++i)
    {
        fin>>x>>y;
        if(x!=y)
            a[x].push_back(y);
    }
    fin.close();
}

inline void Afisare()
{
    int i;
    ofstream fout("bfs.out");
    for(i=1;i<=n;++i)
        fout<<sol[i]<<" ";
    fout<<"\n";
    fout.close();
}

inline void BFS()
{
    int j,i,pr,ul;
    unsigned int k;
    for(i=1;i<=n;++i)
        sol[i]=-1;
    sol[s]=0;
    pr=0;
    ul=-1;
    q[++ul]=s;
    while(pr<=ul)
    {
        i=q[pr];
        pr++;
        for(k=0;k<a[i].size();++k)
        {
            j=a[i][k];
            if(sol[j]==-1)
            {
                sol[j]=1+sol[i];
                q[++ul]=j;
            }
        }
    }
}

int main()
{
    Citire();
    BFS();
    Afisare();
    return 0;
}