#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef set<int> si;
typedef vector<si> vsi;
#define loop(x, i) for (int i = 0; i < x; i++)
#define ALL(x) (x).begin(), (x).end()
typedef pair<int, int> ii;
vector<int> label(int n, int k, vector<int> u, vector<int> v)
{
vsi adj(n);
loop(n - 1, i)
{
int a = u[i], b = v[i];
adj[a].insert(b);
adj[b].insert(a);
}
int root = 0;
if (k == 1'000'000)
{
loop(n, i)
{
if (adj[i].size() > 2)
root = i;
}
}
else
{
if (k == 1000)
{
bool isTask2 = true;
for (int i = 0; i < n - 1; i++)
{
int a = u[i], b = v[i];
if (b > a)
swap(a, b);
if (a != i + 1)
{
isTask2 = false;
break;
}
if (b != i / 2)
{
isTask2 = false;
break;
}
}
if (isTask2)
{
vector<int> labels(n, 0);
for (int i = 1; i < n; i++)
labels[i] = i;
return labels;
}
}
loop(n, i)
{
if (adj[i].size() == 1)
root = i;
}
}
vector<int> labels(n, -1);
queue<ii> q;
int c = 0;
for (int i : adj[root])
{
q.push({i, 1 + 1000 * c});
c++;
}
labels[root] = 0;
while (!q.empty())
{
auto [i, d] = q.front();
q.pop();
labels[i] = d;
for (int j : adj[i])
{
if (labels[j] != -1)
continue;
q.push({j, d + 1});
}
}
return labels;
}
int find_next_station(int s, int t, vector<int> c)
{
if (c.size() == 1)
return c[0];
if (find(ALL(c), t) != c.end())
return t;
vi opt1 = {(s - 1) / 2, s * 2 + 1, s * 2 + 2};
vi opt2 = {(s - 1) / 2, s * 2 + 1};
vi opt3 = {1, 2};
if (c == opt1 || c == opt2 || (s == 0 && c == opt3))
{
int Tlevel = log2(t + 1);
int Slevel = log2(s + 1);
if (Tlevel <= Slevel)
return (s - 1) / 2;
vi branch1 = {s * 2 + 1};
vi branch2 = {s * 2 + 2};
while (true)
{
int si = branch1.size();
bool stop = false;
for (int i = 0; i < si; i++)
{
int v = branch1[i];
if (t == v)
return 2 * s + 1;
if (stop)
continue;
branch1[i] = v * 2 + 1;
branch1.push_back(v * 2 + 2);
if (v > t)
{
stop = true;
}
}
if (stop)
break;
}
if (s == 0)
return 2 * s + 2;
while (true)
{
int si = branch2.size();
bool stop = false;
for (int i = 0; i < si; i++)
{
int v = branch2[i];
if (t == v)
return 2 * s + 2;
if (stop)
continue;
branch2[i] = v * 2 + 1;
branch2.push_back(v * 2 + 2);
if (v > t)
{
stop = true;
}
}
if (stop)
break;
}
return (s - 1) / 2;
}
if (s == 0)
return 1000 * (t / 1000) + 1;
if (t / 1000 != s / 1000 || t < s)
return c[0];
return c.back();
}
