#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    ll n, s, ans = 0;
    cin >> n >> s;
    vector<ll> fact(s);
    fact[0] = 1;
    for(int i = 1; i < s; i++)fact[i] = i * fact[i - 1];
    vector<int> p(s);
    for(int i = 0, S = 0; i < s; i++){
        for(int j = 0; j < s; j++){
            if(S >> j & 1)continue;
            if(n >= fact[s - 1 - i]){
                n -= fact[s - 1 - i];
                continue;
            }
            p[j] = i;
            S |= 1 << j;
            break;
        }
    }
    for(int i = 0, S = 0; i < s; i++){
        for(int j = 0; j < p[i]; j++){
            if(S >> j & 1)continue;
            ans += fact[s - 1 - i];
        }
        S |= 1 << p[i];
    }
    cout << ans << endl;
}