Cod sursa(job #3308222)

Utilizator DasapSapunaru Daniel Dasap Data 23 august 2025 19:11:52
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.72 kb
#include <iostream>
#include<fstream>
#include<vector>
#include<queue>
using namespace std;ifstream fin("bfs.in");ofstream fout("bfs.out");
vector<int>v[100001];
int n,m,d[100001],idx,val,i,a,b;
void bfs(int idx){
    queue<int>q;
    q.push(idx);
    while(!q.empty()){
     int nod=q.front();
     q.pop();
     for(auto vecin:v[nod]){
        if(d[nod]+1<d[vecin]){
            d[vecin]=d[nod]+1;
            q.push(vecin);
        }
     }
    }
    for(int j=1;j<=n;j++)if(d[j]==n+1)d[j]=-1;
}
int main()
{
    fin>>n>>m>>idx;for(i=1;i<=n;i++)d[i]=n+1;d[idx]=0;
    for(i=1;i<=m;i++){
        fin>>a>>b;
        v[a].push_back(b);
    }
    bfs(idx);for(i=1;i<=n;i++)fout<<d[i]<<' ';
    return 0;
}