#include "stations.h"
#include <bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define cmin(a, b) a=min(a, b)
#define cmax(a, b) a=max(a, b)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) (int)x.size()
using namespace std;
vector<int> a;
vector<vector<int>> adj;
int cnt=0;
void dfs(int u, int p=-1) {
for (auto &v: adj[u]) if (v!=p) dfs(v, u);
a[u]=cnt++;
}
vector<int> label(int n, int k, vector<int> u, vector<int> v) {
adj.clear(), adj.resize(n);
for (int i=0; i<n-1; i++) adj[u[i]].pb(v[i]), adj[v[i]].pb(u[i]);
cnt=0, a.clear(), a.resize(n, -1);
dfs(0);
return a;
}
int find_next_station(int s, int t, vector<int> c) {
int best=s;
for (auto &u: c) {
if (t>s) {
if (u>s) return u;
} else if (u>=t) {
cmin(best, u);
}
}
return best;
}
