#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
void setLabel(int u, int par, int f, vector<int> &labels, vector<vector<int>> &adj, int &c) {
if (f) labels[u] = c++;
for (auto v: adj[u]) if (v != par) setLabel(v, u, !f, labels, adj, c);
if (!f) labels[u] = c++;
}
std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
vector<int> labels(n, -1);
vector<vector<int>> adj(n);
int c = 0;
for (int i = 0; i < n - 1; ++i) {
adj[u[i]].push_back(v[i]);
adj[v[i]].push_back(u[i]);
}
setLabel(0, -1, 0, labels, adj, c);
return labels;
}
int find_next_station(int s, int t, std::vector<int> c) {
if (s < c[0]) {
if (t < s || t >= c.back()) return c.back();
auto it = lower_bound(c.begin(), c.end(), t) - c.begin();
return c[it];
} else {
if (t > s || t <= c[0]) return c[0];
auto it = upper_bound(c.begin(), c.end(), t) - c.begin() - 1;
return c[it];
}
}
