#include "highway.h"
#include <bits/stdc++.h>
#define long long long
#define pii pair<int, int>
#define x first
#define y second
using namespace std;
const int N = 2e5 + 5;
int n, m, A, B;
int chk[N], par[N];
vector<int> u, v;
vector<pii> g[N];
void find_pair(int _n, vector<int> _u, vector<int> _v, int _A, int _B) {
n = _n, m = (int)_u.size(), u = _u, v = _v, A = _A, B = _B;
for(int i = 0; i < m; i++) {
g[u[i]].emplace_back(v[i], i);
g[v[i]].emplace_back(u[i], i);
}
int rot = 0;
long mn_dist = ask(vector<int>(m));
vector<int> ans;
for(int _ = 0; _ < 2; _++) {
queue<int> Q;
vector<int> vec;
memset(chk, 0, sizeof chk);
Q.emplace(rot), chk[rot] = 1, par[rot] = rot;
while(!Q.empty()) {
int u = Q.front(); Q.pop();
for(pii v : g[u]) if(!chk[v.x]) {
chk[v.x] = 1, par[v.x] = u;
vec.emplace_back(v.y);
Q.emplace(v.x);
}
}
reverse(vec.begin(), vec.end());
//printf("rot = %d\n", rot);
//for(int i : vec) printf("%d ", i);
//printf("\n");
int l = 0, r = (int)vec.size() - 1;
while(l < r) {
int mid = (l + r) >> 1;
vector<int> now(m);
for(int i = 0; i <= mid; i++) now[vec[i]] = 1;
if(ask(now) > mn_dist) r = mid;
else l = mid + 1;
}
int a = u[vec[r]], b = v[vec[r]];
if(par[b] == a) swap(a, b);
ans.emplace_back(rot = a);
}
//printf("answer = %d %d\n", ans[0], ans[1]);
answer(ans[0], ans[1]);
}
