Cod sursa(job #2102300)

Utilizator MarinPeptenaruMarin Vasile Peptenaru MarinPeptenaru Data 8 ianuarie 2018 17:09:22
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include <bits/stdc++.h>

using namespace std;
ifstream in("bfs.in");
ofstream out("bfs.out");
const int nx=100002;
vector < int > v[nx];
int dist[nx],n,m,start,i,j;
void bfs (int start)
{
    for(int i=1; i<=n; i++)
        dist[i]=INT_MAX;
    dist[start]=0;
    queue < int > q;
    q.push(start);
    while(!q.empty())
    {
        int i=q.front();
        q.pop();
        for(vector < int > :: iterator it=v[i].begin(); it!=v[i].end(); it++)
            if(dist[*it]>dist[i]+1)
            {
                dist[*it]=dist[i]+1;
                q.push(*it);
            }
    }
    for(int i=1; i<=n; i++)
        out<<(dist[i]==INT_MAX? -1:dist[i])<<' ';
}
int main()
{
    in>>n>>m>>start;
    for(;m;m--)
    {
        in>>i>>j;
        v[i].push_back(j);
    }
    bfs(start);
    return 0;
}