Cod sursa(job #2840514)

Utilizator ciobyCiobanu Vlasie cioby Data 27 ianuarie 2022 22:32:06
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.15 kb
#include <fstream>
#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
ifstream fin("bfs.in");
ofstream fout("bfs.out");

typedef struct graf {

    int x;
    graf* a;
}*L;

L a[100001];
int f[100001];
int dist[100001];
queue <int> q;

int n, m, s;

void adaugare(L& dest, int val)
{
    L p = new graf;
    p->a = dest;
    p->x = val;
    dest = p;
}

void citire()
{
    int x, y;
    fin >> n >> m >> s;
    for (int i = 1; i <= m; i++) {
        fin >> x >> y;
        adaugare(a[x], y);
    }
}

void bfs(int nod)
{
    q.push(nod);
    f[nod] = 1;
    while (!q.empty()){
        int k = q.front();
        q.pop();
        for (L p = a[k]; p != NULL; p = p->a)
        {
            if (!f[p->x]) {
                f[p->x] = 1;
                q.push(p->x);
                dist[p->x] = dist[k] + 1;
            }
        }
    }

}

int main()
{
    citire();
    bfs(s);
    for (int i = 1; i <= n; i++)
    {
        if (dist[i] == 0) dist[i] = -1;
    }
    dist[s] = 0;
    for (int i = 1; i <= n; i++)
    {
        fout << dist[i] << ' ';
    }
}