[LeetCode]#728. Self Dividing Numbers

Environment: Python 3.7

Key technique: if not, //, %

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]

Analysis:

1. Input numbers are divided by 10 to get remainder.
2. If remainder =0 is first filter condition, delete 13, 14, 16.
3. If not r is second filter condition, delete 10.
4. Get answer.

Solution:

class Solution:
    def selfDividingNumbers(self, left, right):
ans = []
        for n in range(left, right + 1):
            if self.isDividing(n):
                ans.append(n)
        return ans
        
    def isDividing(self, num):
        temp = num
        while temp:
            div = temp % 10
            if not div or num % div != 0:
                return False
            temp //= 10
        return True

Submission:

Reference:

python程式碼 if not x: 和 if x is not None: 和 if not x is None:使用介紹

https://blog.csdn.net/fuxuemingzhu/article/details/79053113