Cod sursa(job #2640855)

Utilizator PushkinPetolea Cosmin Pushkin Data 8 august 2020 17:00:47
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.74 kb
#include <bits/stdc++.h>
using namespace std;

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

vector<vector<int>> G;
int n;

void read(int &s)
{
    int x, y;
    f>>n>>s>>s;
    G.resize(n+1);
    while(f>>x>>y)
        G[x].push_back(y);
}

vector<int> viz;
queue<int> q;
void BFS(int s)
{
    viz.resize(n+1, -1);
    viz[s]=0;
    q.push(s);
    while(q.size())
    {
        s=q.front();
        q.pop();
        for(auto a:G[s])
            if(viz[a]==-1)
            {
                viz[a]=viz[s]+1;
                q.push(a);
            }
    }
}

int main()
{
    int s;

    read(s);

    BFS(s);
    for(int i=1; i<=n; i++)
        g<<viz[i]<<' ';

    f.close();
    g.close();
    return 0;
}