//나는 가상 소녀들에게 큰 호감이 있습니다.
#include <iostream>
#include <cmath>
#include <algorithm>
#include <stdio.h>
#include <cstring>
#include <string>
#include <cstdlib>
#include <vector>
#include <bitset>
#include <map>
#include <chrono>
#include <functional>
#include <unordered_set>
#include <unordered_map>
#include <numeric>
#include <queue>
#include <ctime>
#include <stack>
#include <set>
#include <list>
#include <deque>
#include <iomanip>
#include <sstream>
#include <fstream>
#include <stdarg.h>
#include <utility>
using namespace std;
#define pb push_back
#define mp make_pair
#define ll long long
#define ull unisgned long long
#define ld long double
#define all(a) a.begin(), a.end()
#define SORT(a) sort(all(a))
#define pii pair<int, int>
#define tii triple<int, int, int>
#define e 1e-7
#define PI acos(-1)
#define sz(a) (int)(a.size())
#define inf 1e17
#define vi vector<int>
#define F first
#define S second
#define rng(x) for(int _ = 0; _ < (x); _++)
#define rngi(i, x) for(int i = 0; i < (x); i++)
#define rngsi(s, i, x) for(int i = (s); i <(x); i++)
#define problem "a"
#pragma comment(linker, "/STACK:36777216")
template<typename A, typename B, typename C>
struct triple {
A X;
B Y;
C Z;
triple(A a = 0, B b = 0, C c = 0) :X(a), Y(b), Z(c) {}
};
template<typename A, typename B, typename C>
triple<A, B, C> make_triple(A a = 0, B b = 0, C c = 0) {
return triple<A, B, C>(a, b, c);
}
template<typename A, typename B, typename C>
bool operator<(const triple<A, B, C>& a, const triple<A, B, C>& b) {
if (a.X != b.X)
return a.X < b.X;
if (a.Y != b.Y)
return a.Y < b.Y;
return a.Z < b.Z;
}
template<typename T, typename SS>
ostream& operator<<(ostream& ofs, const pair<T, SS>& p) {
ofs << "( " << p.F << " , " << p.S << " )";
return ofs;
}
template<typename T>
void print(T a) {
for (auto i : a)
cout << i << ' ';
cout << '\n';
}
template<typename T>
T max(T a, T b, T c) {
return max(a, max(b, c));
}
template<typename T>
T min(T a, T b, T c) {
return min(a, min(b, c));
}
template<typename T, typename D>
D min(T a) {
return *min_element(all(a));
}
template<typename T, typename D>
D max(T a) {
return *max_element(all(a));
}
struct custom_hash {
static uint64_t splitmix64(uint64_t x) {
x += 0x9e3779b97f4a7c15;
x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
return x ^ (x >> 31);
}
size_t operator()(uint64_t x) const {
static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
return splitmix64(x + FIXED_RANDOM);
}
};
#include "highway.h"
vector<vi> idlevel; int mxh = 0;
vector<vi> ids;
vector<vector<pii> > g;
vi pe;
vi usd;
void dfs(int v, int p, int h) {
usd[v] = 1;
mxh = max(mxh, h);
ids[h].push_back(v);
for (auto to : g[v]) if(!usd[to.first]) {
idlevel[h].push_back(to.second);
pe[to.first] = to.second;
dfs(to.first, v, h + 1);
}
}
void find_pair(int n, std::vector<int> u, std::vector<int> v, int a, int b) {
g.resize(n);
int m = sz(u);
rngi(i, m) g[u[i]].push_back({ v[i],i }), g[v[i]].push_back({ u[i],i });
idlevel.assign(n, vi());
ids.assign(n, vi());
pe.assign(n, 0);
mxh = 0;
usd.assign(n, 0);
dfs(0, 0, 0);
ll reg = ask(vi(n - 1, 0));
int l = 0, r = mxh + 1;
auto ok = [&](int x) {
if (x >= mxh) return false;
vi w(n - 1);
for(int i = x; i < mxh; i++)for (auto v : idlevel[i]) w[v] = 1;
ll ans = ask(w);
return ans > reg;
};
while (r - l > 1) {
m = l + r >> 1;
if (ok(m)) l = m; else r = m - 1;
}
int lca = l; if (ok(r)) lca = r;
l = 0, r = sz(ids[lca + 1]);
auto ok2 = [&](int x) {
if (x == sz(ids[lca + 1])) return false;
vi w(n - 1);
rngi(i, x + 1) w[pe[ids[lca + 1][i]]] = 1;
ll ans = ask(w);
return ans > reg;
};
while (r - l > 1) {
m = l + r >> 1;
if (ok2(m)) r = m; else l = m + 1;
}
int id = r; if (ok2(l)) id = l;
int s = ids[lca + 1][id];
idlevel.assign(n, vi());
ids.assign(n, vi());
pe.assign(n, 0);
usd.assign(n, 0);
mxh = 0;
dfs(s, s, 0);
l = 0, r = mxh + 1;
while (r - l > 1) {
m = l + r >> 1;
if (ok(m)) l = m; else r = m - 1;
}
lca = l; if (ok(r)) lca = r;
l = 0, r = sz(ids[lca + 1]);
while (r - l > 1) {
m = l + r >> 1;
if (ok2(m)) r = m; else l = m + 1;
}
id = r; if (ok2(l)) id = l;
// cout << lca << '\n';
// rngi(i, mxh) print(ids[i]);
//print(ids[lca + 1]);
answer(s, ids[lca + 1][id]);
}
/*
9 8 1 2 2 5
0 1 0 2 1 3 3 8 3 4 3 6 6 5 8 7
*/
