#include "stations.h"
#include <vector>
#include<bits/stdc++.h>
using namespace std;
using ll = int;
std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
vector<ll> labels(n);
iota(labels.begin(),labels.end(),0);
vector<vector<ll>> con(n);
for(ll i = 0;i<n-1;i++){
con[u[i]].push_back(v[i]);
con[v[i]].push_back(u[i]);
}
fill(labels.begin(),labels.end(),-1);
/*for(ll i = 0;i<n;i++){
if (con[i].size()==1&&labels[i]==-1){
ll cur = i;
ll it = 0;
while(cur!=-1){
labels[cur] = it++;
ll nxt = -1;
for(ll j : con[cur]) if (labels[j]==-1) nxt = j;
cur = nxt;
}
}
}*/
/*ll rt = 0;
for(ll i = 0;i<n;i++) if(con[i].size()>2) rt = i;
labels[rt] = 0;
ll gp = 0;
for(ll i : con[rt]){
ll g = (++gp)*1000;
ll x = i;
while(x!=-1){
labels[x] = g++;
ll nw = -1;
for(ll j : con[x]){
if(labels[j]==-1){
nw = j;
}
}
x = nw;
}
}*/
vector<vector<ll>> ch(n);
vector<ll> sz(n,1);
{
function<void(ll,ll)> dfs;
dfs = [&](ll i, ll p){
for(ll j : con[i]) if(j!=p){
ch[i].push_back(j);
dfs(j,i);
sz[i]+=sz[j];
}
};
dfs(0,-1);
}
{
function<void(ll,ll,ll)> dfs;
dfs = [&](ll i, ll it,ll pos){
if (pos){
labels[i] = it+sz[i]-1;
}else{
labels[i] = it++;
}
for(ll j : ch[i]){
dfs(j, it, pos^1);
it += sz[j];
}
};
dfs(0,0,0);
}
//for(ll i = 0;i<n;i++) cerr << labels[i] << " \n"[i+1==n];
return labels;
}
int find_next_station(int s, int t, std::vector<int> C) {
deque<ll> c(C.begin(),C.end());
//cerr << s << " " << t << " :";
//for(ll i : c) cerr << " " << i;
//cerr << "\n";
/*s++;t++;
ll lgs = __lg(s), lgt = __lg(t);
if (lgs<lgt){
ll x = t>>(lgt-lgs);
if (s==x){
return (t>>(lgt-lgs-1))-1;
}
}
return (s>>1)-1;*/
/*if (t>s) return s+1;
else return s-1;*/
/*ll gs = s/1000;
ll gt = t/1000;
if (gs==0){
for(ll i : c){
if (i/1000==gt) return i;
}
}else if(gs==gt){
if(s>t){
for(ll i : c){
if (i<s) return i;
}
}else{
for(ll i : c){
if (i>s) return i;
}
}
}else{
for(ll i : c){
if (i<s) return i;
}
}*/
sort(c.begin(),c.end());
if(s==0){
for(ll i : c) if(i>=t) return i;
}else{
if (s<c[0]){
ll pa = c.back();c.pop_back();
if (t<s||c.empty()||t>c.back()) return pa;
for(ll i : c) if(i>=t) return i;
}else{
ll pa = c.front();c.pop_front();
if (t>s||c.empty()||t<c.front()) return pa;
reverse(c.begin(),c.end());
for(ll i : c) if(i<=t) return i;
}
}
return -1;
}
