#include <bits/stdc++.h>
using namespace std;
long long dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0};
long long kaijo[2000010];
long long gcd(long long a, long long b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
bool prime(long long a) {
  if (a == 1) return false;
  for (long long i = 2; i * i <= a; i++) {
    if (a % i == 0) return false;
  }
  return true;
}
void init_fact() {
  kaijo[0] = 1;
  for (long long i = 1; i <= 2000000; i++) {
    kaijo[i] = kaijo[i - 1] * i;
    kaijo[i] %= 1000000007;
  }
}
long long modpow(long long a, long long b) {
  if (b == 0) return 1;
  if (b % 2) return modpow(a, b - 1) * a % 1000000007;
  long long memo = modpow(a, b / 2);
  return memo * memo % 1000000007;
}
long long comb(long long a, long long b) {
  if (!kaijo[0]) init_fact();
  return kaijo[a] * modpow(kaijo[a - b], 1000000007 - 2) % 1000000007 *
         modpow(kaijo[b], 1000000007 - 2) % 1000000007;
}
long long inv(long long x) {
  x = modpow(x, 1000000007 - 2);
  return x;
}
bool kosa(double ax, double ay, double bx, double by, double cx, double cy,
          double dx, double dy) {
  double ta = (cx - dx) * (ay - cy) + (cy - dy) * (cx - ax);
  double tb = (cx - dx) * (by - cy) + (cy - dy) * (cx - bx);
  double tc = (ax - bx) * (cy - ay) + (ay - by) * (ax - cx);
  double td = (ax - bx) * (dy - ay) + (ay - by) * (ax - dx);
  return tc * td < 0 && ta * tb < 0;
}
string n;
long long k, m;
long long f(long long i, long long x) {
  if (x == 0) return 0;
  if (i >= m) return 0;
  long long res = 0;
  if (n[i] == '0') {
    res += 9 * comb(m - i - 1, x - 1) * pow(9, x - 1);
    return res + f(i + 1, x);
  } else {
    res += (9 - (n[i] - '0')) * comb(m - i - 1, x - 1) * pow(9, x - 1);
    return res + f(i + 1, x - 1);
  }
}
signed main() {
  cin >> n >> k;
  m = n.size();
  if (m < k) cout << 0 << endl;
  init_fact();
  long long ans = comb(m, k) * pow(9, k);
  ans -= f(0, k);
  cout << ans << endl;
  return 0;
}
