#include "chameleon.h"
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define pb push_back
#define all(x) x.begin(), x.end()
#define en cout << '\n'
#define ff first
#define ss second
#define pii pair<int,int>
#define vi vector<int>
const int N = 1e6+100, M = 5e3+10, K = 52, MX = 30;
namespace {
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int rn(int l, int r){
return uniform_int_distribution<int>(l,r)(rng);
}
vector<bool> done;
void answer(int x, int y){
if(done[x] || done[y]) return;
done[x] = done[y] = 1;
// cerr << x << ' ' << y << '\n';
Answer(x, y);
}
int query(vi &A, int l, int r, int other){
vi v;
for(int j = l; j <= r; ++j) v.pb(A[j]);
v.pb(other);
return Query(v);
}
void dfs(int v, int col, vi &vis, vector<vi> &g){
vis[v] = col;
for(int u: g[v]){
if(!vis[u]){
dfs(u, 3 - col, vis, g);
}else{
assert(vis[u] != vis[v]);
}
}
}
}
void Solve(int n) {
vi loves(2*n+1);
done.resize(2*n + 1);
vector<vi> g(2*n + 1);
for(int i = 1; i <= 2*n; ++i){
vector<int> vis(2*n+1);
for(int j = 1; j < i; ++j){
if(!vis[j]){
dfs(j, 1, vis, g);
}
}
vi A, B;
for(int j = 1; j < i; ++j){
if(vis[j] == 1) A.pb(j);
else B.pb(j);
}
for(int rep = 0; rep < 2; ++rep){
int last = int(A.size()) - 1;
for(int rp = 0; rp < 3; ++rp){
int l = 0, r = last, res = -1;
if(l > r || query(A, l, r, i) == r - l + 2) break;
while(l <= r){
int mid = l+r>>1;
if(query(A, mid, r, i) < r - mid + 2){
res = mid;
l = mid + 1;
}else{
r = mid - 1;
}
}
assert(res != -1);
g[i].pb(A[res]);
g[A[res]].pb(i);
last = res - 1;
}
swap(A, B);
}
}
for(int i = 1; i <= n*2; ++i){
if(g[i].size() == 1){
answer(g[i][0], i);
}else{
vi S = {g[i][0], g[i][1], g[i][2]};
vi A = {S[0], S[1], i};
vi B = {S[0], S[2], i};
vi C = {S[1], S[2], i};
int a = Query(A);
int b = Query(B);
int c = Query(C);
if(a == 1) loves[i] = S[2];
if(b == 1) loves[i] = S[1];
if(c == 1) loves[i] = S[0];
}
}
for(int i = 1; i <= n*2; ++i){
if(g[i].size() == 1){
answer(g[i][0], i);
}else{
for(int u: g[i]){
if(loves[u] != i && loves[i] != u){
answer(u, i);
}
}
}
}
}
