Cod sursa(job #2185595)

Utilizator Daria09Florea Daria Daria09 Data 24 martie 2018 18:00:20
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 <deque>
#define NMAX 100005
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
bool viz[NMAX];
int n,m,s,dist[NMAX];
vector <int> a[NMAX];
deque <int> coada;
void read()
{
    f>>n>>m>>s;
    for(int i=1;i<=m;i++)
    {
        int x,y;
        f>>x>>y;
        a[x].push_back(y);
    }
    f.close();
}
void bfs()
{
    for(int i=1;i<=n;i++)dist[i]=-1;
    coada.push_back(s);
    viz[s]=1;
    dist[s]=0;
    while(!coada.empty())
    {
        int p=coada.front();
        for(int i=0;i<a[p].size();i++)
            if(viz[a[p][i]]==0)
        {
            viz[a[p][i]]=1;
            coada.push_back(a[p][i]);
            dist[a[p][i]]=dist[p]+1;
        }
        coada.pop_front();
        ++p;
    }
    for(int i=1;i<=n;i++)
        g<<dist[i]<<" ";
    g<<'\n';
}
int main()
{
    read();
    bfs();
    return 0;
}