#include "grader.h"
#include <bits/stdc++.h>
using namespace std;
int findEgg(int N, vector<pair<int, int>> bridges) {
vector<vector<int>> adj(N);
for (auto [a, b] : bridges) {
a--, b--;
adj[a].push_back(b), adj[b].push_back(a);
}
vector<int> num(N);
int ct = 0;
function<void(int, int)> fvii = [&](int cur, int par) {
num[cur] = ct++;
for (auto a : adj[cur])
if (a != par)
fvii(a, cur);
};
fvii(0, 0);
int l = 0, r = N - 1;
while (l < r) {
// return 0;
// cout << l << " " << r << "\n";
int mid = (l + r) / 2;
vector<int> qry;
for (int i = 0; i < N; i++)
if (l <= num[i] && num[i] <= mid)
qry.push_back(i + 1);
int x = query(qry);
// cout << x << "\n";
if (x == 1) {
r = mid;
} else {
l = mid + 1;
}
}
return find(num.begin(), num.end(), l) - num.begin() + 1;
}
