Cod sursa(job #2838302)

Utilizator cdenisCovei Denis cdenis Data 23 ianuarie 2022 12:54:10
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.84 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <bitset>

using namespace std;

ifstream fin("bfs.in");
ofstream fout("bfs.out");

const int MAX=1e5+5;
int n,m,s,a,b,pasi[MAX];
bitset < MAX > viz;
queue < int > q;
vector < int > v[MAX];

void BFS(int s)
{
    q.push(s);
    viz[s]=1;
    pasi[s]=1;
    while(!q.empty())
    {
        int nod=q.front();
        q.pop();
        for(auto vec : v[nod])
            if(!viz[vec])
            {
                pasi[vec]=pasi[nod]+1;
                viz[vec]=1;
                q.push(vec);
            }
    }
}

int main()
{
    fin >> n >> m >> s;
    while(m--)
    {
        fin >> a >> b;
        v[a].push_back(b);
    }
    BFS(s);
    for(int i=1;i<=n;i++)
        fout << (pasi[i]==0?-1:pasi[i]-1) << " ";
    return 0;
}