//https://i...content-available-to-author-only...u.ru/5344-5.html
#include <vector>
#include <iostream>
#include <iomanip>
#include <algorithm>

using namespace std;

using ullong = unsigned long long int;

class tooLong
{
public:
    static const unsigned int magic = 1000000000, digs = 9;
    tooLong(unsigned int n = 0)
    {
        while(n)
        {
            a.push_back(n % tooLong::magic);
            n /= tooLong::magic;
        }
        if (a.empty()) a.push_back(0);
    };

    friend tooLong operator *(const tooLong& a, const tooLong& b);
    friend ostream& operator <<(ostream&os, const tooLong& a);

    bool operator !() const { return !(a.size() == 1 && a[0] == 0); }

private:
    vector<unsigned int> a;
    static vector<unsigned int> sum(const vector<unsigned int>& a, const vector<unsigned int>& b,
                                    unsigned int shift_b = 0);
    static vector<unsigned int> mul(const vector<unsigned int>& a, unsigned int b);


};

vector<unsigned int> tooLong::sum(const vector<unsigned int>& a, const vector<unsigned int>& b,
                                  unsigned int shift_b)
{
    size_t sz = max(a.size(),b.size()+shift_b);
    vector<unsigned int> r(sz);
    unsigned int c = 0;
    for(unsigned int i = 0; i < sz; ++i)
    {
        r[i] = (i < a.size() ? a[i] : 0) +
            (i < shift_b ? 0 : i < b.size()+shift_b ? b[i-shift_b] : 0)
            + c;
        c = r[i] / tooLong::magic;
        r[i] %= tooLong::magic;
    }
    if (c) r.push_back(c);
    return r;
}

vector<unsigned int> tooLong::mul(const vector<unsigned int>& a, unsigned int b)
{
    vector<unsigned int> r;
    ullong c = 0;
    for(int i = 0; i < a.size(); ++i)
    {
        ullong s = ullong(a[i]) * ullong(b) + c;
        c = s / magic;
        s %= magic;
        r.push_back((unsigned int)s);
    }
    while(c)
    {
        r.push_back(c % magic);
        c /= magic;
    }
    return r;
}


tooLong operator *(const tooLong& aa, const tooLong& bb)
{
    vector<unsigned int> r;
    const vector<unsigned int>& a = (aa.a.size() > bb.a.size()) ? bb.a : aa.a;
    const vector<unsigned int>& b = (aa.a.size() > bb.a.size()) ? aa.a : bb.a;

    for(int i = 0; i < a.size(); ++i)
    {
        vector<unsigned int> s = tooLong::mul(b,a[i]);
        r = tooLong::sum(r,s,i);
    }
    tooLong res;
    res.a = r;
    return res;
}

ostream& operator <<(ostream&os, const tooLong& a)
{
    os << a.a[a.a.size()-1];
    os << setfill('0');
    for(int i = (int)a.a.size()-2; i >= 0; --i)
         os << setw(tooLong::digs) << a.a[i];
    return os;
}


tooLong F(int N)
{
    static tooLong L[21] = {0};
    if ( !L[N] ) return L[N];
    tooLong R = 1;
    if (N == 1) return R;
    for(int m = 1; m < N; ++m)
        R = R*F(m);
    L[N] = R*N;
    return L[N];
}

int main()
{
    //for(int N = 1; N <= 20; ++N)
    //    cout << F(N) << "\n";
    int N;
    cin >> N;
    //N = 20;
    cout << F(N);
}