#include "minerals.h"
#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
#define all(x) x.begin(), x.end()
#define len(x) (int)(x).size()
#define x first
#define y second
template <typename T>
ostream &operator<<(ostream &o, const vector<T> &t);
template <typename T, typename T2>
ostream &operator<<(ostream &o, const pair<T, T2> &t);
template <typename T, typename T2>
ostream &operator<<(ostream &o, const pair<T, T2> &t)
{
  return o << "{" << t.x << "," << t.y << "}";
}
template <typename T>
ostream &operator<<(ostream &o, const vector<T> &t)
{
  o << "[";
  for (int i = 0; i < len(t); i++)
  {
    cout << (i ? "," : "") << t[i];
  }
  return o << "]";
}
set<int> unknown, device;
int myQuery(int x)
{
  if (device.count(x))
    device.erase(x);
  else
    device.insert(x);
  return Query(x);
}
void Solve(int n)
{
  unknown.clear();
  device.clear();
  for (int i = 1; i <= 2 * n; i++)
    unknown.insert(i);
  while (len(unknown))
  {
    int v = *unknown.begin();
    Query(v);
    for (auto u : unknown | ranges::views::drop(1))
    {
      if (Query(u) == 1)
      {
        Answer(v, u);
        unknown.erase(u);
        unknown.erase(v);
        Query(u);
        break;
      }
      Query(u);
    }
    Query(v);
  }
  // while (len(unknown))
  // {
  //   for (auto u : unknown | ranges::views::drop(1))
  //   {
  //     if (Query(u) != len(device))
  //     {
  //       int v = Query(u);
  //       // for(int i = 0;i < n)
  //     }
  //   }
  //   Query(v);
  // }
}
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