Cod sursa(job #3206374)

Utilizator suimerchantsui merchant suimerchant Data 22 februarie 2024 15:16:02
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>
#include <vector>
using namespace std;


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


int n,m,s;


int d[100005];


vector <int> g[100005];


struct el
{
    int nod;
    int lg;
};


queue <el> q;


void read()
{
    fin>>n>>m>>s;
    int x,y;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y;
        g[x].push_back(y);
    }
}


void bfs(int sursa)
{
    q.push({sursa,0});
    while(!q.empty())
    {
        int nod=q.front().nod;
        int lg=q.front().lg;
        q.pop();
        for(auto vecin: g[nod])
        {
            if(!d[vecin] && vecin!=sursa)
            {
                d[vecin]=lg+1;
                q.push({vecin,lg+1});
            }
        }
    }
    for(int i=1;i<=n;i++)
    {
        if(d[i]==0 && i!=sursa)
            fout<<-1<<" ";
        else fout<<d[i]<<" ";
    }
}


int main()
{
    read();
    bfs(s);
    return 0;
}