#include "grader.h"
#include <bits/stdc++.h>
using namespace std;
const int maxn = 517;
vector<int> g[maxn], f;
void dfs(int u, int pre){
f.push_back(u);
for(int v: g[u]){
if(v != pre) dfs(v, u);
}
}
int findEgg(int N, vector <pair<int, int>> bridges){
int n = N;
f.clear();
for(auto [u, v]: bridges){
g[u].push_back(v);
g[v].push_back(u);
}
f.push_back(0);
dfs(1, 0);
for(int i = 1; i <= n; i++) g[i].clear();
int l = 1, r = n - 1, ans = n;
while(l <= r){
int mid = (l + r) / 2;
vector<int> v;
for(int i = 1; i <= mid; i++) v.push_back(f[i]);
if(query(v) == 1){
ans = mid;
r = mid - 1;
}
else l = mid + 1;
}
return f[ans];
}
