python 整数中1出现的次数

把整数转换为字符串

用count计数

# -*- coding:utf-8 -*-
class Solution:
    def NumberOf1Between1AndN_Solution(self, n):
        # write code here
        count = 0
        for i in range(1,n+1):
            s = str(i)
            count += s.count('1')
        return count