#include "stations.h"
#include <iostream>
#include <bits/stdc++.h>
#define fi first
#define se second
using namespace std;
int inf = 1e9 + 7;
vector<vector<int>> g;
vector<int> par;
vector<set<int>> st;
void dfs(int v, int p = -1) {
par[v] = p;
st[v].insert(v);
for (auto u : g[v]) {
if (u != p) {
dfs(u, v);
for (auto el : st[u]) {
st[v].insert(el);
}
}
}
}
vector<int> label(int n, int k, vector<int> v, vector<int> u) {
vector<int> res(n);
g.assign(n, {});
par.assign(n , -1);
st.assign(n, {});
for (int i = 0; i < n - 1; i++) {
g[v[i]].push_back(u[i]);
g[u[i]].push_back(v[i]);
}
dfs(0);
for (int i = 0; i < n; i++) {
for (auto el : st[i]) {
res[i] += (1 << el);
}
}
return res;
}
bool subs(set<int> s1, set<int> s2) {
bool ok = 1;
for (auto el : s1) {
if (s2.find(el) == s2.end()) {
ok = 0;
}
}
return ok;
}
int find_next_station(int s, int t, vector<int> c) {
if (c.size() == 1) {
return c[0];
}
set<int> sst;
for (int i = 0; i < 8; i++) {
if ((s >> i) & 1) {
sst.insert(i);
}
}
set<int> tst;
for (int i = 0; i < 8; i++) {
if ((t >> i) & 1) {
tst.insert(i);
}
}
int p = -1;
for (auto el : c) {
set<int> elst;
for (int i = 0; i < 8; i++) {
if ((el >> i) & 1) {
elst.insert(i);
}
}
if (subs(sst, elst)) {
p = el;
}
if (subs(tst, elst) && p != el) {
return el;
}
}
return p;
}
