#include <fstream>
#include <iomanip>
#include <string>
#include <vector>

void mult (std::vector<unsigned long long>& num, unsigned int m) {
    unsigned long long mem = 0;
    unsigned long long thirteen_digits = 10000000000000;
    for (size_t i = 0; i < num.size(); ++i) {
        unsigned long long sum = num[i] * m + mem;
        num[i] = sum % thirteen_digits;
        mem = sum / thirteen_digits;
    }
    if (mem > 0) {
        num.push_back(mem % thirteen_digits);
    }
}

std::vector<unsigned long long> factorial(int n) {
    std::vector<unsigned long long> res = {1};
    res.reserve(1 << 16);
    for (unsigned int i = 1; i <= n; ++i) {
        mult(res, i);
    }
    return res;
}

int main() {
    std::ifstream in("input.txt");
    std::ofstream out("output.txt");
    std::string s;
    in >> s;
    std::vector<unsigned long long> res = factorial(std::stoi(s));
    out << res.back();
    for (auto i = ++res.rbegin(); i != res.rend(); ++i) {
        out << std::setfill('0') << std::setw(13) << *i;
    }
    out << "\n";
    in.close();
    out.close();
}