#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll INF = LLONG_MAX / 40 - 100;
ll mod = 1e9 + 7;
long long dx[] = {-1, 0, 1, 0}, dy[] = {0, 1, 0, -1};
long long ddx[] = {-1, 0, 1, -1, 1, -1, 0, 1},
          ddy[] = {1, 1, 1, 0, 0, -1, -1, -1};
vector<ll> prime;
class fact {
 public:
  long long fmod = 1e9 + 7;
  vector<long long> fac, inv;
  fact(long long n, long long Mod = 1e9 + 7) {
    fmod = Mod;
    fac = vector<long long>(n + 1, 0);
    inv = vector<long long>(n + 1, 0);
    fac[0] = 1;
    for (long long i = 1; i < n + 1; i++) fac[i] = fac[i - 1] * i % fmod;
    for (long long i = 0; i < n + 1; i++) inv[i] = fact::POW(fac[i], fmod - 2);
  }
  ll nCr(ll n, ll r) {
    if (n < r) return 0;
    return (fac[n] * inv[r] % fmod) * inv[n - r] % fmod;
  }
  ll POW(ll a, ll b) {
    ll c = 1;
    while (b > 0) {
      if (b & 1) {
        c = a * c % fmod;
      }
      a = a * a % fmod;
      b >>= 1;
    }
    return c;
  }
};
template <class T = ll>
T in() {
  T x;
  cin >> x;
  return (x);
}
void DEBUG(vector<long long> a) {
  for (long long i = 0; i < a.size(); i++) cout << a[i] << " ";
  cout << endl;
}
void EMP(long long x) { cout << "!!!" << x << "!!!" << endl; }
ll GCD(ll a, ll b) {
  ll c;
  while (b != 0) {
    c = a % b;
    a = b;
    b = c;
  }
  return a;
}
ll LCM(ll a, ll b) { return (a / GCD(a, b)) * b; }
void PRI(ll n) {
  bool a[n + 1LL];
  for (long long i = 0; i < n + 1LL; i++) {
    a[i] = 1LL;
  }
  for (long long i = 2; i < n + 1LL; i++) {
    if (a[i]) {
      prime.push_back(i);
      ll b = i;
      while (b <= n) {
        a[b] = 0;
        b += i;
      }
    }
  }
}
template <typename T>
bool chmin(T& a, T b) {
  bool res = false;
  if (a > b) a = b, res = true;
  return res;
}
template <typename T>
bool chmax(T& a, T b) {
  bool res = false;
  if (a < b) a = b, res = true;
  return res;
}
bool isSqrt(ll a) { return (pow(sqrt(a), 2) == a) ? 1 : 0; }
void YesNo(bool a) {
  if (a)
    cout << "Yes";
  else
    cout << "No";
  cout << endl;
}
void yesno(bool a) {
  if (a)
    cout << "yes";
  else
    cout << "no";
  cout << endl;
}
void YESNO(bool a) {
  if (a)
    cout << "YES";
  else
    cout << "NO";
  cout << endl;
}
long long extGCD(long long a, long long b, long long& x, long long& y) {
  if (b == 0) {
    x = 1;
    y = 0;
    return a;
  }
  long long d = extGCD(b, a % b, y, x);
  y -= a / b * x;
  return d;
}
long long mul(long long a, long long b, long long mod) {
  long long keta[20] = {};
  long long c = b;
  long long now = 0;
  while (c != 0ll) {
    keta[now] = c % 10;
    c /= 10;
    now++;
  }
  long long res = 0;
  for (long long i = 19; i >= 0; --i) {
    res *= 10;
    res %= mod;
    res += keta[i] * a % mod;
  }
  return res % mod;
}
ll POW(ll a, ll b) {
  ll c = 1;
  while (b > 0) {
    if (b & 1) {
      c = a * c % mod;
    }
    a = a * a % mod;
    b >>= 1;
  }
  return c;
}
long long dp[305][305];
void solve() {
  dp[0][0] = 1;
  for (long long(i) = (0); (i) < (304); (i)++) {
    for (long long(j) = (0); (j) < (i + 1); (j)++) {
      dp[i + 1][j] += dp[i][j];
      dp[i + 1][j + 1] += dp[i][j];
    }
  }
  string s;
  cin >> s;
  long long k;
  cin >> k;
  long long n = s.size();
  long long ans = 0;
  if (n - 1 >= k) ans += dp[n - 1][k] * POW(9, k);
  if (k == 1) {
    ans += s[0] - '0';
  } else if (k == 2) {
    ans += (s[0] - '0' - 1) * (n - 1) * 9;
    bool flag = false;
    for (long long(i) = (1); (i) < (n); (i)++) {
      if (!flag)
        ans += s[i] - '0';
      else
        ans += 9;
      if (s[i] != '0') flag = true;
    }
  } else {
    ans += (s[0] - '1') * dp[n - 1][2] * 9 * 9;
    bool flag = false;
    for (long long(i) = (1); (i) < (n); (i)++) {
      bool f2 = false;
      long long tmp = 0;
      for (long long(j) = (i + 1); (j) < (n); (j)++) {
        if (!f2)
          tmp += s[i] - '1';
        else
          tmp += 9;
        if (s[j] != '0') f2 = true;
        if (flag) {
          ans += 9 * 9;
        } else if (f2) {
          ans += (s[i] - '0') * 9;
        } else {
          ans += (s[i] - '1') * 9;
          ans += (s[j] - '0');
        }
        if (s[j] != '0') f2 = true;
      }
      if (s[i] != '0') flag = true;
    }
  }
  cout << ans << endl;
}
signed main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  solve();
}
