剑指Offer 43

 1 # -*- coding:utf-8 -*-
 2 class Solution:
 3     def NumberOf1Between1AndN_Solution(self, n):
 4         cnt = 0
 5         m = 1
 6         while m <= n: 
 7             a = n // m
 8             b = n % m
 9             mm = 0
10             if a % 10 == 1:
11                 mm = b+1
12             cnt += (a+8) // 10 * m + mm
13             m *= 10
14         return cnt
15         # write code here