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#include <bits/stdc++.h>
using namespace std;
class Task {
public:
void solve() {
read_input();
print_output(get_result());
}
private:
// numarul maxim de noduri
static constexpr int NMAX = (int)1e5 + 5; // 10^5 + 5 = 100.005
// n = numar de noduri, m = numar de muchii/arce
int n, m;
// adj[node] = lista de adiacenta a nodului node
// exemplu: daca adj[node] = {..., neigh, ...} => exista muchia (node, neigh)
vector<int> adj[NMAX];
// nodul sursa in parcurgerea BFS
int source;
void read_input() {
ifstream fin("bfs.in");
fin >> n >> m >> source;
for (int i = 1, x, y; i <= m; i++) {
fin >> x >> y; // muchie (x, y)
adj[x].push_back(y);
// orientat
// adj[y].push_back(x);
}
fin.close();
}
void bfs(int source, vector<int>& d, vector<int>& parents,
vector<int>& visited) {
queue<int> q;
d[source] = 0;
parents[source] = -1;
q.push(source);
// color the node
visited[source] = 1;
while (!q.empty()) {
int node = q.front();
q.pop();
// use node here!
for (auto& neigh : adj[node]) {
if (visited[neigh] == 0) { // not yet visited
d[neigh] = d[node] + 1;
parents[neigh] = node;
visited[neigh] = 1;
q.push(neigh);
}
}
visited[node] = 2;
}
}
vector<int> get_result() {
// TODO: Faceti un BFS care sa construiasca in d valorile cerute:
// * d[node] = numarul minim de muchii de parcurs de la nodul `source` la
// nodul `node`
// * d[source] = 0
// * d[node] = -1, daca nu exista drum de la source la node
// *******
// ATENTIE: nodurile sunt indexate de la 1 la n.
// *******
vector<int> d(n + 1);
// add by me:
vector<int> parents(n + 1);
vector<int> visited(n + 1);
for (int i = 1; i <= n; i++) {
d[i] = -1;
parents[i] = -1;
visited[i] = 0;
}
bfs(source, d, parents, visited);
return d;
}
void print_output(const vector<int>& d) {
ofstream fout("bfs.out");
for (int node = 1; node <= n; node++) {
fout << d[node] << (node == n ? '\n' : ' ');
}
fout.close();
}
};
// [ATENTIE] NU modifica functia main!
int main() {
// * se aloca un obiect Task pe heap
// (se presupune ca e prea mare pentru a fi alocat pe stiva)
// * se apeleaza metoda solve()
// (citire, rezolvare, printare)
// * se distruge obiectul si se elibereaza memoria
auto* task = new (nothrow) Task(); // hint: cppreference/nothrow
if (!task) {
cerr << "new failed: WTF are you doing? Throw your PC!\n";
return -1;
}
task->solve();
delete task;
return 0;
}