Cod sursa(job #2781509)

Utilizator guzgandemunteIonescu Laura guzgandemunte Data 9 octombrie 2021 18:04:55
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.18 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <cctype>
#define VMAX 100000

using namespace std;

int V, E, x, y, src;
vector <int> adj[VMAX];
bool vis[VMAX];
int d[VMAX];

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

int readInt() {
    char ch;
    int res = 0;

    while (!isdigit(ch = fin.get()));

    do {
    res = 10 * res + ch - '0';
    } while (isdigit(ch = fin.get()));

    return res;
}

void BFS(int src)
{
    int u;
    queue <int> q;

    q.push(src);
    d[src] = 1;

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

        for (auto w:adj[u])
            if (!d[w])
            {
                d[w] = d[u] + 1;
                q.push(w);
            }
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    fin.tie(0);
    fout.tie(0);

    V = readInt(), E = readInt(), src = readInt();

    while (E--)
    {
        x = readInt();
        y = readInt();
        adj[x - 1].push_back(y - 1);
    }

    BFS(src - 1);

    for (int i = 0; i < V; ++i)
        fout << d[i] - 1 << " ";

    fin.close();
    fout.close();
    return 0;
}