n=gets.to_i
k=gets.to_i
s=n.to_s
a=s.chars.map(&:to_i)
z=s.size
def f1(n,s,a,z)
  if n==0
    return 0
  else
    return (z-1)*9+a[0]
  end
end
def f2(n,s,a,z)
  if z==1
    return 0
  else
    c=(z-2)*(z-1)/2*81+(z-1)*9*(a[0]-1)
    a.delete_at(0)
    z=a.size
    s=a.join
    n=s.to_i
    c+=f1(n,s,a,z)
    return c
  end
end
def f3(n,s,a,z)
  if z<=2
    return 0
  else
    c=(z-3)*(z-2)*(z-1)/6*729+(z-2)*(z-1)/2*81*(a[0]-1)
    a.delete_at(0)
    z=a.size
    s=a.join
    n=s.to_i
    c+=f1(n,s,a,z)
    return c
  end
end
if k==1
  puts (z-1)*9+a[0]
elsif k==2
  puts f2(n,s,a,z)
else
  puts f3(n,s,a,z)
end

