Cod sursa(job #2883196)

Utilizator ioana0211Ioana Popa ioana0211 Data 1 aprilie 2022 11:56:56
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>
#define NMAX 100005
using namespace std;

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

int n, m, s, x, y, nivel[NMAX];
vector<int> ad[NMAX];
queue<int> q;

void bfs(int start_node)
{
    for(int i=1; i<=n; i++)
        nivel[i]=-1;
    nivel[start_node]=0;
    q.push(start_node);
    while(!q.empty())
    {
        int nod=q.front();
        q.pop();
        for(auto &vecin: ad[nod])
            if(nivel[vecin]==-1)
            {
                nivel[vecin]=nivel[nod]+1;
                q.push(vecin);
            }
    }
}
int main()
{
    fin>>n>>m>>s;
    for(int i=1; i<=m; i++)
    {
        fin>>x>>y;
        ad[x].push_back(y);
    }
    bfs(s);
    for(int i=1; i<=n; i++)
        fout<<nivel[i]<<" ";
    return 0;
}