/*
TASK:minitime
LANG:C++
*/

#include<iostream>
using namespace std;
int main()
{
    int n,k=0,p=0,s,p1=0;
    cin>>n;
    if(n==0)cout<<0<<endl;
    else{
    if(n<=3)k=1;
    else k=2;
    if(n%2==0)p=n/2;
    else p1=n/2+1;
    if(p1>p)cout<<p1+k<<endl;
    else cout<<p+k<<endl;}
    
}
