#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 1000000007;
// constexpr int MOD = 998244353;
constexpr int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
constexpr int dy8[] = {1, 1, 0, -1, -1, -1, 0, 1}, dx8[] = {0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U> inline bool chmax(T &a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U> inline bool chmin(T &a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

int main() {
  ll n; int s; cin >> n >> s;
  vector<int> p(s), b(s);
  iota(ALL(b), 0);
  vector<ll> fact(s + 1, 1);
  FOR(i, 1, s + 1) fact[i] = fact[i - 1] * i;
  REP(i, s) {
    REP(j, s - i) {
      if (fact[s - i - 1] > n) {
        p[i] = b[j];
        b.erase(b.begin() + j);
        break;
      }
      n -= fact[s - i - 1];
    }
  }
  // REP(i, s) cout << p[i] << " \n"[i + 1 == s];
  vector<int> sigma(s);
  REP(i, s) sigma[p[i]] = i;
  ll ans = 0;
  REP(i, s) {
    int gt = 0;
    FOR(j, i + 1, s) gt += sigma[j] < sigma[i];
    ans += fact[s - i - 1] * gt;
  }
  cout << ans << '\n';
  return 0;
}