Cod sursa(job #2779700)

Utilizator Maniu_DianaManiu Maria Diana Maniu_Diana Data 4 octombrie 2021 19:08:59
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.93 kb
#include <bits/stdc++.h>

using namespace std;

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

vector < int > L[100005];

queue < int > Q;

int n, m, s, dp[100005];

void read()
{
    fin >> n >> m >> s;
    int x, y;
    for(int i = 1; i <= m; i ++)
    {
        fin >> x >> y;
        L[x].push_back(y);
    }
    for(int i = 1; i <= n; i ++)
    {
        dp[i] = 1e9;
    }
}

void BFS()
{
    Q.push(s);
    dp[s] = 0;
    while(!Q.empty())
    {
        int nod = Q.front();
        Q.pop();
        for(int i = 0; i < L[nod].size(); i ++)
        {
            int vecin = L[nod][i];
            if(dp[vecin] == 1e9)
            {
                dp[vecin] = 1 + dp[nod];
                Q.push(vecin);
            }
        }
    }
    for(int i = 1; i <= n; i ++)
    {
        fout << (dp[i] == 1e9 ? -1 : dp[i]) << " ";
    }
}

int main()
{
    read();
    BFS();
    return 0;
}