Cod sursa(job #2420060)

Utilizator AndreiDeltaBalanici Andrei Daniel AndreiDelta Data 10 mai 2019 13:20:16
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.85 kb
#include <bits/stdc++.h>
#define Dim 100008
using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
int N,M,S,Ans[Dim],a,b;
bool viz[Dim];

vector <int> V[Dim];

void BFS()
{
    queue <int> qu;
    qu.push(S);
    viz[S]=1;
    while(!qu.empty())
    {
        int nod=qu.front();
        qu.pop();
        viz[nod]=1;
        for(unsigned int i=0;i<V[nod].size();i++)
        {
            int vecin=V[nod][i];
            if(!viz[vecin])
            {
                viz[vecin]=1;
                Ans[vecin]=Ans[nod]+1;
                qu.push(vecin);
            }
        }
    }
}

int main()
{
    f>>N>>M>>S;
    for(int i=1;i<=M;i++)
    {
        f>>a>>b;
        V[a].push_back(b);
    }
    BFS();
    for(int i=1;i<=N;i++)
    if(Ans[i]==0&&i!=S) g<<-1<<" ";
    else g<<Ans[i]<<" ";

    return 0;
}