Cod sursa(job #2270622)

Utilizator PaduraruCristianPaduraru Cristian Daniel PaduraruCristian Data 27 octombrie 2018 11:54:48
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.95 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

ifstream f("bfs.in");
ofstream g("bfs.out");

queue <int> p;
vector <int> q[100001];
bool vizitat[100001];
int grad[100001];
int n,m,s;

void BFS(int nod)
{
    int i;
    while(p.empty()==false)
    {
        nod=p.front();
        p.pop();
        vizitat[nod]=true;
        for(i=0; i<q[nod].size(); i++)
        {
            if(vizitat[q[nod][i]]==false)
            {
                grad[q[nod][i]]=grad[nod]+1;
                p.push(q[nod][i]);
                vizitat[q[nod][i]]=true;
            }
        }
    }
}

int main()
{
    f>>n>>m>>s;
    int i,x,y;
    for(i=1; i<=m; i++)
    {
        f>>x>>y;
        q[x].push_back(y);
    }
    p.push(s);
    BFS(s);
    for(i=1;i<=n;i++)
    {
        if(vizitat[i]==false)
            g<<"-1 ";
        else
            g<<grad[i]<<" ";
    }
    return 0;
}