#include "stations.h"
#include <bits/stdc++.h>
using namespace std;
int timer = -1;
void dfs(int node, int prev, vector<vector<int>> &adj, vector<int> &tin, vector<int> &tout) {
tin[node] = ++timer;
for (auto &neighbour : adj[node]) {
if (neighbour == prev) continue;
dfs(neighbour, node, adj, tin, tout);
}
tout[node] = timer;
}
vector<int> label(int n, int k, vector<int> u, vector<int> v) {
vector<int> ans(n); for (int i = 0; i < n; i++) ans[i] = i;
return ans;
}
bool dfs(int node, int prev, int src, vector<vector<int>> &adj, int targ) {
if (node == targ) return true;
bool h = false;
for (auto &neighbour : adj[node]) {
if (neighbour == prev) continue;
if (neighbour == src) continue;
h |= dfs(neighbour, node, src, adj, targ);
}
return h;
}
const int N = 1001;
int find_next_station(int s, int t, std::vector<int> c) {
vector<vector<int>> adj(N);
for (int i = 0; i < N-1; i++) {
int u = i+1, v = i/2;
adj[u].push_back(v);
adj[v].push_back(u);
}
for (auto &neighbour : c) {
if (dfs(neighbour, -1, s, adj, t)) return neighbour;
}
assert(false);
return -1;
}
