#include <bits/stdc++.h>
#include "trilib.h"
using namespace std;
typedef long long ll;
typedef long double ld;
const int MOD = (int)1e9 + 7;
const int MAXN = (int)107;
const int infint = (int)1e9;
int n;
vector<int> u, d, ans;
/*int get_n()
{
int x;
cin >> x;
return x;
}
int is_clockwise(int x, int y, int z)
{
cout << x << " " << y << " " << z << endl;
int ans;
cin >> ans;
return ans;
}
void give_answer(int t)
{
cout << t << endl;
return;
}*/
bool cw(int i, int j)
{
return is_clockwise(1, i, j);
}
bool ccw(int i, int j)
{
return !is_clockwise(1, i, j);
}
vector<int> convex(vector<int> v)
{
vector<int> ans;
for (auto u : v)
{
while(ans.size() >= 2 && is_clockwise(ans[ans.size() - 2], ans.back(), u))
ans.pop_back();
ans.push_back(u);
}
return ans;
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
n = get_n();
for (int i = 3; i <= n; i++)
if(is_clockwise(1, 2, i))
d.push_back(i);
else
u.push_back(i);
sort(d.begin(), d.end(), ccw);
sort(u.begin(), u.end(), ccw);
d.push_back(2);
u.push_back(1);
d = convex(d), u = convex(u);
for (auto x : d)
ans.push_back(x);
for (auto x : u)
ans.push_back(x);
/*for (auto x : ans)
cout << x << " ";
cout << endl;
ans = convex(ans);
for (auto x : ans)
cout << x << " ";
cout << endl;*/
ans = convex(ans);
deque<int> qs;
for (auto x : ans)
qs.push_back(x);
bool did = false;
while(!did)
{
did = 1;
int a = qs.back(); qs.pop_back();
if(is_clockwise(qs.back(), a, qs.front()))
did = 0;
else
qs.push_back(a);
a = qs.front();
qs.pop_front();
if(!is_clockwise(qs.front(), a, qs.back()))
did = 0;
else
qs.push_front(a);
}
give_answer(qs.size());
}
