tj

tj

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll N=1e6+10;
const ll M=5050;
ll n,ans;
int dfs(ll idx)
{
    for(ll i=idx/2;i>=0;i--)
    {
        if(i>1)
        {
            ans+=dfs(i);
        }
        else
        {
            ans+=1;
        }
    }
    return 0;
}
int main()
{
    cin>>n;
    dfs(n);
    cout<<ans;
    return 0;
}