#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
void calc_size(vector<vector<int>> & adj, vector<int> & sz, vector<bool> & v, int i) {
v[i] = true;
for (int n: adj[i]) {
if (v[n]) continue;
calc_size(adj, sz, v, n);
sz[i] += sz[n];
}
}
void calc_label(vector<vector<int>> & adj, vector<int> & sz, vector<bool> & v, int i, int l, int r, vector<int> & label, bool high) {
v[i] = true;
label[i] = high ? --r : l++;
for (int n: adj[i]) {
if (v[n]) continue;
calc_label(adj, sz, v, n, l, l + sz[n], label, !high);
l += sz[n];
}
}
vector<int> label(int n, int k, vector<int> u, vector<int> v) {
vector<vector<int>> adj(n);
for (int i = 0; i < n - 1; i++)
{
adj[u[i]].push_back(v[i]);
adj[v[i]].push_back(u[i]);
}
vector<int> sz(n, 1);
vector<bool> v_(n, false);
calc_size(adj, sz, v_, 0);
vector<int> label(n);
v_ = vector<bool>(n, false);
calc_label(adj, sz, v_, 0, 0, n, label, false);
return label;
}
int find_next_station(int s, int t, vector<int> c) {
if (c.size() == 1) return c[0];
sort(c.begin(), c.end());
if (s == 0) {
for (int i = 0; i < c.size() - 1; i++)
{
if (c[i] <= s && s < c[i + 1]) return c[i];
}
return c.back();
}
if (c[0] < s) {
if (s < t || c[1] > t) return c.front();
for (int i = 1; i < c.size() - 1; i++)
{
if (s >= c[i] && s < c[i + 1]) return c[i];
}
return c.back();
} else {
if (s > t || c[1] < t) return c.back();
for (int i = c.size() - 2; i >= 1; i--)
{
if (s <= c[i] && s > c[i + 1]) return c[i];
}
return c.front();
}
}
