#include "speedrun.h"
#include "bits/stdc++.h"
using namespace std;
#define pb push_back
#define sz(a) (int)a.size()
vector<int> st;
void dfsHint(int u, int par, vector<vector<int>>& adj, vector<int>& parent){
st.pb(u);
parent[u] = par;
for(int v: adj[u]){
if(v == par)continue;
dfsHint(v, u, adj, parent);
}
}
void assignHints(int subtask , int n, int a[], int b[]){
setHintLen(20);
vector<vector<int>> adj(n + 1);
for(int i = 1;i <= n - 1; ++i){
adj[a[i]].pb(b[i]);
adj[b[i]].pb(a[i]);
}
vector<int> right_neighbor(n + 1, 0), parent(n + 1, 0), left_child(n + 1, 0);
dfsHint(1, 0, adj, parent);
vector<int> nxt(n + 1, 0);
for(int i = 0;i < sz(st); ++i){
nxt[st[i]] = st[(i + 1) % sz(st)];
}
for(int i = 1;i <= n; ++i){
int idx = 1;
for(int j = 9;j >= 0; --j){
if(parent[i] & (1 << j))setHint(i, idx, 1);
++idx;
}
for(int j = 9;j >= 0; --j){
if(nxt[i] & (1 << j))setHint(i, idx, 1);
++idx;
}
}
}
int cnt;
void dfs(int u, vector<bool>& vis, int need){
if(!vis[u])--cnt;
vis[u] = true;
if(!cnt)exit(0);
int par = 0, nxt = 0, idx = 1;
for(int j = 9;j >= 0; --j){
if(getHint(idx))par += (1 << j);
++idx;
}
for(int j = 9;j >= 0; --j){
if(getHint(idx))nxt += (1 << j);
++idx;
}
if(need == -1)need = nxt;
int x = goTo(need);
if(x){
dfs(need, vis, -1);
}else{
assert(par != 0);
goTo(par);
dfs(par, vis, need);
}
}
void speedrun(int subtask, int n, int start){
int l = getLength();
vector<bool> vis(n + 1, false);
cnt = n;
dfs(start, vis, -1);
}
