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.
Input: left = 1, right = 22 Output: [1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 22]
1 <= left <= right <= 10000.
Intuition and Algorithm\n
For each number in the given range, we will directly test if that number is self-dividing.\n
By definition, we want to test each whether each digit is non-zero and divides the number. For example, with
128, we want to test
d != 0 && 128 % d == 0 for
d = 1, 2, 8. To do that, we need to iterate over each digit of the number.
A straightforward approach to that problem would be to convert the number into a character array (string in Python), and then convert back to integer to perform the modulo operation when checking
n % d == 0.
We could also continually divide the number by 10 and peek at the last digit. That is shown as a variation in a comment.\n\n
Time Complexity: , where is the number of integers in the range , and assuming is bounded. (In general, the complexity would be .)\n
Space Complexity: , the length of the answer.\n
Analysis written by: @awice.\n