[hdu 3652] B-number

Problem Description
A wqb-number, or B-number for short, is a non-negative integer whose decimal form contains the sub- string “13” and can be divided by 13. For example, 130 and 2613 are wqb-numbers, but 143 and 2639 are not. Your task is to calculate how many wqb-numbers from 1 to n for a given integer n.

Input
Process till EOF. In each line, there is one positive integer n(1 <= n <= 1000000000).

Output
Print each answer in a single line.

Sample Input

13
100
200
1000

Sample Output

1
1
2
2

题意:找出1~n范围内含有13并且能被13整除的数字的个数

思路:使用记忆化深搜来记录状态,配合数位DP来解决

#include 
#include 
#include 
using namespace

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