题目描述
Problem Statement
Find the number of integers between 1 and K (inclusive) satisfying the following condition, modulo 10^9 + 7:
- The sum of the digits in base ten is a multiple of D.
Input
Input is given from Standard Input in the following format:
K
D
Output
Print the number of integers satisfying the condition, modulo 10^9 + 7.
Constraints
- All values in input are integers.
- $1 \leq K < 10^{10000}$
- $1 \leq D \leq 100$
Sample Input 1
30
4
Sample Output 1
6
Those six integers are: 4, 8, 13, 17, 22 and 26.
Sample Input 2
1000000009
1
Sample Output 2
2
Be sure to print the number modulo 10^9 + 7.
Sample Input 3
98765432109876543210
58
Sample Output 3
635270834
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分
样例输入
30
4
样例输出
6