...

#include<iostream>
using namespace std;
int cnt = 0;
int jjjj(int x){
cnt++;
if(x == 1) return 0;
for(int i = 1;i <= x / 2;i++){
jjjj(i);
}
}
int main(){
int n;
cin >> n;
jjjj(n);
cout << cnt;
return 0;
}