#include <vector>
#include <iostream>
#include <algorithm>
#include <cassert>
std::vector<int> find_reachable(std::vector<int> r, std::vector<int> u, std::vector<int> v, std::vector<int> c) {
int n = (int) r.size();
std::vector<int> ans(r.size(), 1);
std::vector<bool> haveKey(n, false);
std::vector<std::vector<int>> unlock(n);
std::vector<bool> explored(n, false);
std::vector<bool> vis(n, false);
int m = (int) u.size();
std::vector<std::vector<std::pair<int, int>>> g(n);
for (int i = 0; i < m; i++) {
g[u[i]].push_back({v[i], c[i]});
g[v[i]].push_back({u[i], c[i]});
}
auto explore = [&](int start) { // un din asta am voie sa fac in O(n)
for (int i = 0; i < n; i++) {
haveKey[i] = false;
vis[i] = false;
unlock[i].clear();
}
std::vector<int> reach;
reach.push_back(start);
vis[start] = true;
while (!reach.empty()) {
int u = reach.back();
reach.pop_back();
int key = r[u];
for (const auto &[v, t] : g[u]) {
if (!vis[v]) {
if (haveKey[t]) {
reach.push_back(v);
vis[v] = true;
} else {
unlock[t].push_back(v);
}
}
}
if (haveKey[key]) {
continue;
}
haveKey[key] = true;
for (const auto &u : unlock[key]) {
if (!vis[u]) {
vis[u] = true;
reach.push_back(u);
}
}
}
return std::count(vis.begin(), vis.end(), true);
};
std::vector<int> answer(n);
int mini = n + 1;
for (int i = 0; i < n; i++) {
answer[i] = explore(i);
mini = std::min(mini, answer[i]);
}
std::vector<int> ret;
for (int i = 0; i < n; i++) {
if (answer[i] == mini) {
ret.push_back(i);
}
}
return ret;
}
