#include <bits/stdc++.h>
#include "highway.h"
using namespace std;
using ll = long long;
using pii = pair<int, int>;
vector<vector<int>> adj;
int last;
void dfs(int n, int p=-1) {
last = n;
for (auto x : adj[n]) {
if (x==p) continue;
dfs(x, n);
}
}
void find_pair(int n, vector<int> U, vector<int> V, int A, int B) {
int m = U.size();
vector<int> edges;
vector<int> query(m, 0);
ll w = ask(query);
int l = 0, r = m-1;
int ans;
while (l <= r) {
int mm = (l+r)/2;
for (int i=l; i<=mm; i++) {
query[i] = 1;
}
ll w2 = ask(query);
if (w2 > w) {
r = mm-1;
ans = mm;
}
else {
l = mm+1;
}
for (int i=0; i<m; i++) {
query[i] = 0;
}
}
int e = U[ans];
answer(e, e+w/A);
}
