#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <cassert>

#define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl;
#define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using namespace std;
typedef long long ll;

ll fac[21];

void init(){
    fac[0] = 1;
    for(int i = 1; i <= 20; i++) {
        fac[i] = fac[i-1]*i;
        assert(fac[i] < __LONG_LONG_MAX__);
    }
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    init();
    ll n, s; cin >> n >> s;
    vector<int> idx(s);
    vector<int> p(s);
    vector<bool> used(s, false);
    for(int i = 0; i < s; i++){
        ll m = n/fac[s-i-1];
        n %= fac[s-i-1];
        int cnt = 0;
        for(int j = 0; ; j++){
            if(!used[j]) {
                if(cnt == m){
                    used[j] = true;
                    p[i] = j;
                    idx[j] = i;
                    break;
                }
                cnt++;
            }
        }
    }
    ll ans = 0;
    for(int i = 0; i < s; i++){
        int inv_cnt = 0;
        for(int j = i+1; j < s; j++){
            if(idx[i] > idx[j]) inv_cnt++;
        }
        ans += fac[s-i-1]*inv_cnt;
    }
    cout << ans << endl;
}