#include <bits/stdc++.h>
#include "grader.h"
#define F first
#define S second
#define V vector
#define PB push_back
#define EB emplace_back
#define MP make_pair
#define ALL(v) (v).begin(), (v).end()
#define debug(x) cerr << "LINE(" << __LINE__ << "): " << #x << " is " << x << endl
using namespace std;
typedef long long ll;
typedef pair<int, int> pi;
typedef V<int> vi;
const int INF = 1e9 + 7, N = 520;
V<int> G[N];
vi q;
void init(int n) {
for(int i = 1; i <= n; i++) {
G[i].clear();
}
}
void dfs(int u, int p = 0) {
q.PB(u);
for(int v:G[u]) if(v != p)
dfs(v, u);
}
int findEgg(int n, V<pi> es) {
init(n);
for(pi p:es) G[p.F].PB(p.S), G[p.S].PB(p.F);
q.clear();
dfs(1);
int lb = 0, rb = n - 1;
while(lb <= rb) {
int mb = (lb + rb) / 2;
vi ask;
for(int j = 0; j <= mb; j++)
ask.PB(q[j]);
if(query(ask)) rb = mb - 1;
else lb = mb + 1;
}
//debug(lb);
return q[lb];
}
