Cod sursa(job #2915260)

Utilizator andreipirjol5Andrei Pirjol andreipirjol5 Data 22 iulie 2022 10:27:40
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.19 kb
#include <cstdio>
#include <queue>

using namespace std;
FILE *fin, *fout;

#define NMAX 100000
vector <int> graph[NMAX + 5];
vector <int> dist;
bool viz[NMAX + 5];

queue <int> q;
int n;
void bfs(int node)
{
    int i;
    for(i = 0; i < n; i++)
        dist.push_back(-1);

    dist[node] = 0;
    viz[node] = 1;

    q.push(node);

    while(!q.empty())
    {
        node = q.front();
        q.pop();

        for(int i = 0; i < graph[node].size(); i++)
        {
            int neigh = graph[node][i];
            if(dist[neigh] == -1 or dist[neigh] > dist[node] + 1)
            {
                dist[neigh] = dist[node] + 1;
                viz[neigh] = 1;
                q.push(neigh);
            }
        }
    }
}

int main()
{
    fin = fopen("bfs.in", "r");
    fout = fopen("bfs.out", "w");

    int m, s, i;
    fscanf(fin, "%d%d%d", &n, &m, &s);
    int x, y;
    dist.reserve(n + 1);

    for(i = 0; i < m; i++)
    {
        fscanf(fin, "%d%d", &x, &y);
        graph[x].push_back(y);
    }

    bfs(s);

    for(i = 1; i <= n; i++)
        fprintf(fout, "%d ", dist[i]);

    fclose(fin);
    fclose(fout);
    return 0;
}