#include<bits/stdc++.h>
#include "grader.h"
#define INF 1e18
#define fi first
#define se second
#define FOR(i, k, n) for(ll i = k; i <= n; i++)
#define FOR1(i, k, n) for(ll i = k; i >= n; i--)
#define pb push_back
#define fastio ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define vi vector<int>
#define pii pair<int, int>
#define vii vector<pii>
#define ll long long
#define vll vector<ll>
#define pll pair<ll, ll>
#define re return 0
#define mii map<int, int>
#define input "chinaflu.inp"
#define output "chinaflu.out"
#define rf freopen(input, "r", stdin); freopen(output, "w", stdout)
using namespace std;
const int maxn = 1e5 + 5;
const int mod = 1e9 + 9;
const int base = 998244353;
void add(int &a, int b)
{
a += b;
if(a >= mod) a -= mod;
if(a < 0) a += mod;
}
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l, int r)
{
return uniform_int_distribution<int>(l, r) (rd);
}
vi adj[600];
vi vv;
void DFS(int u, int par)
{
vv.pb(u);
for(auto v : adj[u])
{
if(v == par)
continue;
DFS(v, u);
}
}
int findEgg(int n, vii adj1)
{
vv.clear();
FOR(i, 1, n)
adj[i].clear();
for(auto x : adj1)
{
int u = x.fi, v = x.se;
adj[u].pb(v);
adj[v].pb(u);
}
DFS(1, 0);
vi ask;
int l = 0, r = n - 1, vt = -1;
while(l <= r)
{
int mid = (l + r) >> 1;
ask.clear();
FOR(i, 0, mid)
ask.pb(vv[i]);
bool ok = query(ask);
if(n == 16 || n == 512)
{
if(l + 1 == r)
{
if(ok == 1)
vt = l;
else
vt = r;
break;
}
}
if(ok == 1)
{
vt = mid;
r = mid - 1;
}
else
l = mid + 1;
}
return vv[vt];
}
