#include "stations.h"
#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define vi vector<int>
#define f0r(i,n) for(int i = 0; i<n; i++)
#define FOR(i, k, n) for(int i = k; i<n; i++)
#define dout(x) cout<<x<<' '<<#x<<'\n';
#define vout(x) for(auto u : x)cout<<u<<' '; cout<<'\n';
#define vb vector<bool>
using namespace std;
const int mxn = 1005;
vector<vi>adj(mxn);
std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
f0r(i,n){
adj[i].clear();
}
vi deg(n);
f0r(i,n-1){
adj[u[i]].pb(v[i]);
adj[v[i]].pb(u[i]);
deg[u[i]]++;
deg[v[i]]++;
}
std::vector<int> labels(n);
for (int i = 0; i < n; i++) {
labels[i] = i + 1;
}
return labels;
}
int find_next_station(int s, int t, std::vector<int> c) {
// cout<<s<<' '<<t<<'\n';
int os = s; int ot = t;
int ds = 0; int dt = 0;
f0r(i, 30){
if((1 << i) & s){
ds = i;
}
if((1<<i) & t){
dt = i;
}
}
int lca;
while(ds != dt){
if(dt > ds){
t = t/2;
dt--;
}
else{
s = s/2;
ds--;
}
}
while(s != t){
s/=2; t/=2;
}
lca = s;
// dout(lca);
s = os;
t = ot;
vi path;
path.pb(s);
while(s != lca){
s/=2;
path.pb(s);
}
vi p2;
p2.pb(t);
while(t != lca){
t /= 2;
p2.pb(t);
}
p2.pop_back();
reverse(p2.begin(), p2.end());
for(auto u : p2){
path.pb(u);
}
// vout(path);
f0r(i, path.size()){
if(path[i] == os)return path[i+1];
}
return c[0];
}
