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

#define M 1000000007
#define pb emplace_back
#define f first
#define s second
#define rep(i, st, ed) for(ll i=st; i<ed; ++i)
#define repn(i, st, ed) for(ll i=st; i<=ed; ++i)
#define repb(i, ed, st) for(ll i=ed; i>=st; --i)
#define all(v) v.begin(),v.end()
#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );
#define PI acosl(-1.0)
#define mp(a, b) make_pair(a, b)
#define eps 1e-9

typedef long long ll;
typedef unsigned long long int llt;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef vector<ll> vec;
typedef vector<pll> vecp;
typedef map<ll, ll> mpll;


const int N = 1e5 + 10;
const ll INF = 1LL << 60;

template<class T> void chmax(T &a,T b) { if (a<b) a=b;}
template<class T> void chmin(T &a,T b) { if (a>b) a=b;}

template <typename A, typename B>
string to_string(pair<A, B> p);
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
 
string to_string(const string& s) {
  return '"' + s + '"';
}
 
string to_string(const char* s) {
  return to_string((string) s);
}
 
string to_string(bool b) {
  return (b ? "true" : "false");
}
 
string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
 
template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}
 
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
 
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
 
void debug_out() { cerr << endl; }
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << to_string(H) << endl;
  debug_out(T...);
}
#define LOCAL 3
#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:" << endl, debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif


void solve()
{
	string n;
	cin>>n;
	ll k;
	cin>>k;
	ll len = n.length();
	if(k == 1){
		ll ans = (len - 1)*9;
		ans += n[0] - '0';
		cout<<ans<<endl;
	}
	else if(k == 2){
		ll ans = ((len-1)*(len-2)) / 2;
		ans *= 9*9;
		ll l = n[0] - '0';
		ans += (l-1)*(len-1)*9;
		rep(i, 1, len){
			ll c = n[i] - '0';
			ans += c;
			if(c != 0){
				ans += (len-i-1)*9;
				break;
			}
		}
		cout<<ans<<endl;
	}else if(k == 3){
		ll ans = ((len-1)*(len-2)*(len-3)) / (3*2);
		ans *= 9*9*9;
		ll l = n[0] - '0';
		ans += (l-1)*(((len-1)*(len-2)) / 2) * 9 * 9;
		rep(i, 1, len-1){
			ll c = n[i] - '0';
			if(c == 0) continue;
			ans += (c-1)*(len-1-i) * 9;
			rep(j, i+1, len){
				ans += n[j] - '0';
				ll z = n[j] - '0';
				if(z != 0){
					ans += (len-1-j) * 9;
					break;
				}
			}
			if(c != 0){
				ans += (((len-i-1)*(len-i-2)) / 2 ) * 9 * 9;
				break;
			}
		}
		cout<<ans<<endl;
	}
}


int main()
{
    ll Tests = 1;
    //cin>>Tests;
    while(Tests--)
    {
        solve();
    }
    return 0;
}

Measured memory_bytes: 256