#include <bits/stdc++.h>
#include "minerals.h"
using namespace std;
typedef long long ll;
typedef double dl;
typedef vector<int> vi;
typedef vector<vector<int>> vii;
typedef vector<ll> vl;
typedef vector<bool> vb;
typedef pair<int,int> pii;
typedef pair<ll, ll> pll;
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define gcd(a,b) __gcd(a,b)
#define lcm(a,b) (a*(b/gcd(a,b)))
#define file(); freopen("input.txt", "r", stdin);freopen("output.txt", "w", stdout);
#define spc " "
#ifdef ONLINE_JUDGE
#define debarr(array)
#define deb(x)
#else
#define debarr(array) for(int w = 0; w < array.size(); w++) cerr << #array << "-" << w << " = " << array[w] << endl;
#define deb(x) cerr << #x << " = " << x << endl;
#endif
const double PI = acos(-1);
const int MOD = 1000000007;
const int inf = (2147483647);
const double EPS = 1e-6;
const int MAXN = 1e5+10;
void Solve(int N) {
int n = N*2;
vector<vii> arr((N+10)*20, vii(2));
int idx = 0, pushTo = 0;
int last = 0;
for(int i = 1; i <= n; i++){
int now = Query(i);
if(now==last){
arr[pushTo][1].push_back(i);
Query(i);
}else{
arr[pushTo][0].push_back(i);
last = now;
}
}
pushTo++;
// Took 2N operations
// Two group differented
stack<pii> order;
order.push({0, 0});
while(!order.empty()){
vii x = arr[order.top().ff]; int gone = order.top().ss; order.pop();
int sz = x[0].size();
if(sz<=1) continue;
int m = (sz)/2;
for(int i = 0; i < m; i++) arr[pushTo][gone].push_back(x[gone][i]);
for(int i = m; i < sz; i++) last = Query(x[gone][i]), arr[pushTo+1][gone].push_back(x[gone][i]);
for(auto y: x[!gone]){
int now = Query(y);
if(now==last){
arr[pushTo][!gone].push_back(y); Query(y);
}else{
arr[pushTo+1][!gone].push_back(y);
}
last = now;
}
order.push({pushTo, gone});
order.push({pushTo+1, !gone});
pushTo+=2;
}
for(auto x: arr){
if(x[0].size()==1){
Answer(x[0][0], x[1][0]);
}
}
return;
}
