#include <bits/stdc++.h>
int solve(int a, std::string str, int k) {
  int m = str[str.length() - a] - '0';
  if (!m) solve(a - 1, str, k);
  switch (k) {
    case 1:
      return m + 9 * (a - 1);
      break;
    case 2:
      return (m - 1) * (a - 1) * 9 + (a - 1) * (a - 2) / 2 * 81 +
             solve(a - 1, str, 1);
      break;
    case 3:
      return (m - 1) * (a - 1) * (a - 2) / 2 * 81 +
             (a - 1) * (a - 2) * (a - 3) / 6 * 729 + solve(a - 1, str, 2);
      break;
  }
}
int main(int argc, char *argv[]) {
  std::string s;
  int k;
  std::cin >> s >> k;
  std::cout << solve(s.length(), s, k) << std::endl;
  return 0;
}
