#include <bits/stdc++.h>
#define eps 1e-9;
using namespace std;
typedef long long ll;
typedef long double ld;
ll res1, res2;
ll mas[(ll)1e6];
map<pair<ll,ll>,ll> countMap;

int main()
{
    cin.sync_with_stdio(false);
    cout.sync_with_stdio(false);
    ll N;
    cin >> N;
    countMap[{1,1}]=1;
    mas[1]=1;
    for(ll n=2; n<=N; n++){
        res2=0;
        for (ll rest=n; rest>0; rest--)
            if (rest<n-rest)
                countMap[{n, n-rest}]=mas[rest];
            else
                for(map<pair<ll,ll>,ll>::iterator it = countMap.lower_bound({rest, 1}); it!=countMap.upper_bound({rest, n-rest-1}); ++it)
                    countMap[{n, n-rest}]+=(*it).second;
        countMap[{n,n}]=1;
        for (map<pair<ll,ll>,ll>::iterator it = countMap.lower_bound({n, 0}); it!=countMap.upper_bound({n,n}); ++it)
            res2+=(*it).second;
        mas[n]=res2;
    }
    cout << endl << endl << N << "  :  " << res2 << endl << endl;
}