Find the number of integers between 1 and N (inclusive) that contains exactly K non-zero digits when written in base ten.

-----Constraints-----
- $1 \leq N < 10^{100}$
- $1 \leq K \leq 3$

-----Input-----
Input is given from Standard Input in the following format:
N
K

-----Output-----
Print the count.

-----Sample Input-----
100
1

-----Sample Output-----
19

The following 19 integers satisfy the condition:
- 1,2,3,4,5,6,7,8,9,10,20,30,40,50,60,70,80,90,100

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