Cod sursa(job #3367567)

Utilizator lucainfoOlteanu Luca lucainfo Data 8 octombrie 2026 17:34:55
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.98 kb
#include <iostream>
#include <fstream>
#include <queue>

#define INF 2e9

using namespace std;

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

vector < vector < int> > adj;
vector <int> dist;

int n;

void BFS(int source){
    queue<int> q;
    q.push(source);
    dist[source] = 0;
    while(!q.empty())
    {
        int nod =q.front();
        q.pop();
        for( int i: adj[nod])
            if(dist[i] > dist[nod]+1)
            {
                q.push(i);
                dist[i] = dist[nod] +1;
            }
    }
    for(int i=1; i<=n; i++){
        if(dist[i] == INF)
            dist[i] = -1;
        fout<<dist[i]<<" ";
    }
}

int nr = 0;
int m,s;

int main()
{
    fin>>n >>m>>s;

    adj.resize(n+5);
    dist.resize(n+5);
    for (int i=1; i<=n; i++)
        dist[i] = INF;

    for(int i = 1; i<=m; i++)
    {
        int x, y;
        fin>>x>>y;
        adj[x].push_back(y);
    }

    BFS(s);

    return 0;
}