Leetcode:728. Self Dividing Numbers

问题重述：

A self-dividing number is a number that is divisible by every digit it contains.

For example, 128 is a self-dividing number because 128 % 1 == 0, 128 % 2 == 0, and 128 % 8 == 0.

Also, a self-dividing number is not allowed to contain the digit zero.

Given a lower and upper number bound, output a list of every possible self dividing number, including the bounds if possible.

Example 1:
Input:
left = 1, right = 22
Output: [1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 22]
Note:

The boundaries of each input argument are 1 <= left <= right <= 10000.

考虑到时间复杂度的优化应该少用for循环，利用python中参数类型强制转换，且str类型是可迭代类型：

for digit in str(num))

遍历digit寻找全部符合要求的非零数字，采用filter（）函数来代替fo，filter的用法见：http://blog.csdn.net/SeeTheWorld518/article/details/46975897，简化代码：

def selfDividingNumbers(left, right):
dividing = lambda num: '0' not in str(num) and all(num % int(digit) == 0 for digit in str(num))
return filter(dividing, range(left, right + 1))