#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10;
const long long 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 &second) { return '"' + second + '"'; }
string to_string(const char *second) { return to_string((string)second); }
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...);
}
void solve() {
  string n;
  cin >> n;
  long long k;
  cin >> k;
  long long len = n.length();
  if (k == 1) {
    long long ans = (len - 1) * 9;
    ans += n[0] - '0';
    cout << ans << endl;
  } else if (k == 2) {
    long long ans = ((len - 1) * (len - 2)) / 2;
    ans *= 9 * 9;
    long long l = n[0] - '0';
    ans += (l - 1) * (len - 1) * 9;
    for (long long i = 1; i < len; ++i) {
      long long c = n[i] - '0';
      ans += c;
      if (c != 0) {
        ans += (len - i - 1) * 9;
        break;
      }
    }
    cout << ans << endl;
  } else if (k == 3) {
    long long ans = ((len - 1) * (len - 2) * (len - 3)) / (3 * 2);
    ans *= 9 * 9 * 9;
    long long l = n[0] - '0';
    ans += (l - 1) * (((len - 1) * (len - 2)) / 2) * 9 * 9;
    for (long long i = 1; i < len - 1; ++i) {
      long long c = n[i] - '0';
      ans += (c - 1) * (len - 1 - i) * 9;
      for (long long j = i + 1; j < len; ++j) {
        ans += n[j] - '0';
        long long 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() {
  long long Tests = 1;
  while (Tests--) {
    solve();
  }
  return 0;
}
