Cod sursa(job #2785827)

Utilizator World_shifterMurgu Bogdan World_shifter Data 19 octombrie 2021 16:55:59
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.11 kb
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

vector<vector<int> > edges;
vector<int> dist;
int root;

void citire(){
    int n,m,a,b;
    in>>n>>m>>root;
    edges.resize(n);
    dist.resize(n,-1);
    for(int i=0; i<m; i++){
        in>>a>>b;
        a--;b--;
        edges[a].push_back(b);
    }
}

void afis(){
    for(int i=0; i<edges.size(); i++){
        for(int j=0; j<edges[i].size(); j++){
            out<<edges[i][j]+1<<" ";
        }
        out<<"\n";
    }
}

void bfs(int node){
    int next;
    queue<int> q;
    q.push(node);
    dist[node]=0;
    while(!q.empty()){
        node=q.front();
        q.pop();
        for(int i=0; i<edges[node].size(); i++){
            next=edges[node][i];
            if(dist[next]==-1){
                q.push(next);
                dist[next]=dist[node]+1;
            }
        }
    }
}

int main()
{
    int comp_conex=0;
    citire();
    bfs(root-1);
    for(int i=0; i<edges.size(); i++){
        out<<dist[i]<<" ";
    }
    return 0;
}