#include <bits/stdc++.h>
#include "trilib.h"
#define MAXN 100007
using namespace std;
int n;
/*static long long *x, *y;
static int queries=0;
static void init() {
static int is_inited=0;
if (is_inited)
return;
is_inited=1;
assert(scanf("%d", &n)==1);
x=(long long*)malloc((n+1)*sizeof(long long));
y=(long long*)malloc((n+1)*sizeof(long long));
for (int i=1; i<=n; i++){
x[i]=rand()%100+1;
y[i]=rand()%100+1;
//assert(scanf("%lld%lld", &x[i], &y[i])==2);
}
}
int get_n() {
init();
return n;
}
int is_clockwise(int a, int b, int c) {
init();
assert(a>=1 && a<=n);
assert(b>=1 && b<=n);
assert(c>=1 && c<=n);
assert(a!=b && a!=c && b!=c);
queries++;
if(queries == 1000 * 1000 + 1)
printf("Too many queries!");
return (x[b]-x[a])*(y[c]-y[a])-(x[c]-x[a])*(y[b]-y[a])<0;
}
void give_answer(int s) {
init();
printf("%d\n", s);
}*/
vector<int> combine(vector<int> a,vector<int> b){
if(a.empty())return b;
if(b.empty())return a;
for(int test=0;test<100;test++){
int pos=rand()%int(a.size());
vector<int> res;
for(int i=pos;i<a.size();i++)res.push_back(a[i]);
for(int i=0;i<pos;i++)res.push_back(a[i]);
int pos2=rand()%int(b.size());
for(int i=pos2;i<b.size();i++){
while(res.size()>=2 and !is_clockwise(res[res.size()-2],res[res.size()-1],b[i])){
res.pop_back();
}
res.push_back(b[i]);
}
for(int i=0;i<pos2;i++){
while(res.size()>=2 and !is_clockwise(res[res.size()-2],res[res.size()-1],b[i])){
res.pop_back();
}
res.push_back(b[i]);
}
while(res.size()>=3 and !is_clockwise(res[res.size()-2],res[res.size()-1],a[pos])){
res.pop_back();
}
bool b1=false,b2=false;
for(int i=0;i<res.size();i++){
for(int f:a){
if(f==res[i] or f==res[(i+1)%res.size()])continue;
b1=(b1 or is_clockwise(res[i],f,res[(i+1)%res.size()]));
b2=(b2 or !is_clockwise(res[i],f,res[(i+1)%res.size()]));
if(b1 and b2)break;
}
for(int f:b){
if(f==res[i] or f==res[(i+1)%res.size()])continue;
b1=(b1 or is_clockwise(res[i],f,res[(i+1)%res.size()]));
b2=(b2 or !is_clockwise(res[i],f,res[(i+1)%res.size()]));
if(b1 and b2)break;
}
}
if(!(b1 and b2) or test==99){
if(b1 and b2)return {};
return res;
}
}
}
vector<int> solve(vector<int> w){
if(w.size()<=2)return w;
if(w.size()==3){
if(!is_clockwise(w[0],w[1],w[2])){
swap(w[0],w[2]);
}
return w;
}
vector<int> sol;
while(true){
int r1=rand()%int(w.size());
int r2=r1;
while(r2==r1){
r2=rand()%int(w.size());
}
vector<int> l,r;
for(int i=0;i<w.size();i++){
if(i==r1 or i==r2)continue;
if(is_clockwise(w[r1],w[i],w[r2]))l.push_back(w[i]);
else r.push_back(w[i]);
}
vector<int> convL=solve(l);
vector<int> convR=solve(r);
sol=combine(convL,{w[r1],w[r2]});
if(sol.empty())continue;
sol=combine(sol,convR);
if(sol.empty())continue;
break;
}
return sol;
}
vector<int> perm;
int main(){
n=get_n();
for(int i=1;i<=n;i++){
perm.push_back(i);
}
vector<int> res=solve(perm);
give_answer(res.size());
//cout<<queries<<"\n";
return 0;
}
