#include <bits/stdc++.h>
using namespace std;
using lint = long long int;
using pint = pair<int, int>;
using plint = pair<lint, lint>;
struct fast_ios {
  fast_ios() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(20);
  };
} fast_ios_;
template <typename T>
istream &operator>>(istream &is, vector<T> &vec) {
  for (auto &v : vec) is >> v;
  return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &vec) {
  os << "[";
  for (auto v : vec) os << v << ",";
  os << "]";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const deque<T> &vec) {
  os << "deq[";
  for (auto v : vec) os << v << ",";
  os << "]";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const set<T> &vec) {
  os << "{";
  for (auto v : vec) os << v << ",";
  os << "}";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const unordered_set<T> &vec) {
  os << "{";
  for (auto v : vec) os << v << ",";
  os << "}";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const multiset<T> &vec) {
  os << "{";
  for (auto v : vec) os << v << ",";
  os << "}";
  return os;
}
template <typename T>
ostream &operator<<(ostream &os, const unordered_multiset<T> &vec) {
  os << "{";
  for (auto v : vec) os << v << ",";
  os << "}";
  return os;
}
template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &pa) {
  os << "(" << pa.first << "," << pa.second << ")";
  return os;
}
template <typename TK, typename TV>
ostream &operator<<(ostream &os, const map<TK, TV> &mp) {
  os << "{";
  for (auto v : mp) os << v.first << "=>" << v.second << ",";
  os << "}";
  return os;
}
template <typename TK, typename TV>
ostream &operator<<(ostream &os, const unordered_map<TK, TV> &mp) {
  os << "{";
  for (auto v : mp) os << v.first << "=>" << v.second << ",";
  os << "}";
  return os;
}
template <typename T>
void ndarray(vector<T> &vec, int len) {
  vec.resize(len);
}
template <typename T, typename... Args>
void ndarray(vector<T> &vec, int len, Args... args) {
  vec.resize(len);
  for (auto &v : vec) ndarray(v, args...);
}
template <typename T>
bool mmax(T &m, const T q) {
  if (m < q) {
    m = q;
    return true;
  } else
    return false;
}
template <typename T>
bool mmin(T &m, const T q) {
  if (q < m) {
    m = q;
    return true;
  } else
    return false;
}
template <typename T1, typename T2>
pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) {
  return make_pair(l.first + r.first, l.second + r.second);
}
template <typename T1, typename T2>
pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) {
  return make_pair(l.first - r.first, l.second - r.second);
}
int main() {
  string N;
  cin >> N;
  int K;
  cin >> K;
  vector<vector<int>> dp(K + 1, vector<int>(N.length() + 1));
  vector<vector<int>> dpf(K + 1, vector<int>(N.length() + 1));
  dp[0][0] = 1;
  for (int i = (0), i_end_ = (N.length()); i < i_end_; i++) {
    int v = N[i] - '0';
    for (int k = (0), k_end_ = (K); k < k_end_; k++)
      if (!v) dp[k][i + 1] += dp[k][i];
    for (int k = (0), k_end_ = (K); k < k_end_; k++)
      if (v) dpf[k][i + 1] += dp[k][i];
    for (int k = (0), k_end_ = (K); k < k_end_; k++)
      if (v) dpf[k + 1][i + 1] += dp[k][i] * (v - 1);
    for (int k = (0), k_end_ = (K); k < k_end_; k++)
      dp[k + 1][i + 1] += dp[k][i];
    for (int k = (0), k_end_ = (K); k < k_end_; k++) dpf[k][i + 1] += dpf[k][i];
    for (int k = (0), k_end_ = (K); k < k_end_; k++)
      dpf[k + 1][i + 1] += dpf[k][i] * 9;
  }
  cout << accumulate(dp[K].begin(), dp[K].end(), 0) +
              accumulate(dpf[K].begin(), dpf[K].end(), 0)
       << endl;
}
