Introduction

In this blog post, we will explore how to solve the LeetCode problem "2553" 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

Given an array of positive integers nums, return an array answer that consists of the digits of each integer in nums after separating them in the same order they appear in nums. To separate the digits of an integer is to get all the digits it has in the same order. For example, for the integer 10921, the separation of its digits is [1,0,9,2,1]. Example 1: Input: nums = [13,25,83,77] Output: [1,3,2,5,8,3,7,7] Explanation: - The separation of 13 is [1,3]. - The separation of 25 is [2,5]. - The separation of 83 is [8,3]. - The separation of 77 is [7,7]. answer = [1,3,2,5,8,3,7,7]. Note that answer contains the separations in the same order. Example 2: Input: nums = [7,1,3,9] Output: [7,1,3,9] Explanation: The separation of each integer in nums is itself. answer = [7,1,3,9]. Constraints: 1 <= nums.length <= 1000 1 <= nums[i] <= 105

Explanation

Here's an efficient solution to the problem:

• Iterate and Extract: Iterate through the input array nums. For each number, extract its digits.
• Convert to Digits: Convert each number to a string and then iterate over the characters of the string, converting each character back to an integer.

• Append to Result: Append the extracted digits to the answer array.

• Runtime & Storage Complexity: O(N * log(M)), where N is the number of elements in nums and M is the maximum value in nums. The log(M) factor comes from the number of digits in the largest number. Storage complexity is O(K), where K is the total number of digits in all numbers of nums.

Code

    def separate_digits(nums: list[int]) -> list[int]:
    """
    Given an array of positive integers nums, return an array answer that consists of the digits of each integer in nums
    after separating them in the same order they appear in nums.
    To separate the digits of an integer is to get all the digits it has in the same order.
    For example, for the integer 10921, the separation of its digits is [1,0,9,2,1].

    Example 1:
    Input: nums = [13,25,83,77]
    Output: [1,3,2,5,8,3,7,7]
    Explanation:
    - The separation of 13 is [1,3].
    - The separation of 25 is [2,5].
    - The separation of 83 is [8,3].
    - The separation of 77 is [7,7].
    answer = [1,3,2,5,8,3,7,7].

    Example 2:
    Input: nums = [7,1,3,9]
    Output: [7,1,3,9]
    Explanation: The separation of each integer in nums is itself.
    answer = [7,1,3,9].

    Constraints:
    1 <= nums.length <= 1000
    1 <= nums[i] <= 105
    """
    answer = []
    for num in nums:
        for digit in str(num):
            answer.append(int(digit))
    return answer