#include <bits/stdc++.h>
using namespace std;
#define pb push_back
const int N = 1e6;
vector<int> g[N];
int timer = 0, tin[N], tout[N];
void dfs(int v, int p){
tin[v] = timer++;
for(int u: g[v]){
if(u != p) dfs(u, v);
}
tout[v] = timer;
}
vector<int> label(int n, int k, vector<int> u, vector<int> v){
for(int i = 0; i < n-1; ++i) g[u[i]].pb(v[i]), g[v[i]].pb(u[i]);
cout <<"wuw" << endl;
dfs(0, 0);
vector<int> l;
for(int i = 0; i < n; ++i) l.pb(tin[i] * 2000 + tout[i]);
return l;
}
int find_next_station(int s, int t, vector<int> c){
for(int p: c){
if(p==t) return t;
}
int ti = t, to = t % 2000;
int sx = s, sy = s % 2000;
int par = -1;
for(int v: c){
int x = v, y = v % 2000;
if(x <= sx && sy <= y){
par = v;
}
else if(x <= ti && to <= y){
return v;
}
}
return par;
}
