#include<iostream>
#include<set>
#include<vector>
using namespace std;

typedef unsigned long long ull;

int main(){
    ull n;
    int s;
    cin >> n >> s;
    vector<ull> fact(21);
    fact[0] = 1;
    for(int i = 1; i <= 20; i++)    fact[i] = fact[i-1]*i;
    vector<int> origin(s);
    set<int> res;
    for(int i = 1; i <= s; i++) res.insert(i);
    ull acc = 0;
    for(int i = 0; i < s; i++){
        ull sum = 0, unit = fact[s-i-1];
        for(auto it = res.begin(); it != res.end(); it++){
            if(acc+sum+unit > n){
                origin[i] = *it;
                res.erase(it);
                acc += sum;
                break;
            }
            sum += unit;
        }
    }
    vector<int> rev(s);
    for(int i = 0; i < s; i++)  rev[origin[i]-1] = i+1;
    for(int i = 1; i <= s; i++) res.insert(i);
    ull ans = 0;
    for(int i = 0; i < s; i++){
        ull sum = 0, unit = fact[s-1-i];
        for(auto it = res.begin(); it != res.end(); it++){
            if(*it == rev[i]){
                ans += sum;
                res.erase(it);
                break;
            }
            sum += unit;
        }
    }
    cout << ans << endl;
    return 0;
}