Introduction

In this blog post, we will explore how to solve the LeetCode problem "728" using AI. LeetCode is a popular platform for preparing for coding interviews, and with the help of AI tools like Chatmagic, we can generate solutions quickly and efficiently - helping you pass the interviews and get the job offer without having to study for months.

Problem Statement

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. A self-dividing number is not allowed to contain the digit zero. Given two integers left and right, return a list of all the self-dividing numbers in the range [left, right] (both inclusive). Example 1: Input: left = 1, right = 22 Output: [1,2,3,4,5,6,7,8,9,11,12,15,22] Example 2: Input: left = 47, right = 85 Output: [48,55,66,77] Constraints: 1 <= left <= right <= 104

Explanation

Here's the breakdown of the solution:

• Iterate and Check: Iterate through each number within the given range (left to right inclusive).
• Self-Dividing Verification: For each number, check if it's self-dividing by extracting its digits and verifying divisibility. If any digit is zero or the number isn't divisible by a digit, it's not a self-dividing number.

• Collect Results: If a number passes the self-dividing check, add it to the list of self-dividing numbers.

• Runtime Complexity: O(N K), where N is the range (right - left + 1) and K is the maximum number of digits in a number in the range. *Storage Complexity: O(M), where M is the number of self-dividing numbers in the range.

Code

    def selfDividingNumbers(left: int, right: int) -> list[int]:
    """
    Finds all self-dividing numbers in the range [left, right] (inclusive).

    A self-dividing number is a number that is divisible by every digit it contains.
    A self-dividing number is not allowed to contain the digit zero.

    Args:
        left: The left bound of the range (inclusive).
        right: The right bound of the range (inclusive).

    Returns:
        A list of all self-dividing numbers in the range [left, right].
    """
    result = []
    for num in range(left, right + 1):
        is_self_dividing = True
        temp = num
        while temp > 0:
            digit = temp % 10
            if digit == 0 or num % digit != 0:
                is_self_dividing = False
                break
            temp //= 10
        if is_self_dividing:
            result.append(num)
    return result