Introduction

In this blog post, we will explore how to solve the LeetCode problem "1929" 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 integer array nums of length n, you want to create an array ans of length 2n where ans[i] == nums[i] and ans[i + n] == nums[i] for 0 <= i < n (0-indexed). Specifically, ans is the concatenation of two nums arrays. Return the array ans. Example 1: Input: nums = [1,2,1] Output: [1,2,1,1,2,1] Explanation: The array ans is formed as follows: - ans = [nums[0],nums[1],nums[2],nums[0],nums[1],nums[2]] - ans = [1,2,1,1,2,1] Example 2: Input: nums = [1,3,2,1] Output: [1,3,2,1,1,3,2,1] Explanation: The array ans is formed as follows: - ans = [nums[0],nums[1],nums[2],nums[3],nums[0],nums[1],nums[2],nums[3]] - ans = [1,3,2,1,1,3,2,1] Constraints: n == nums.length 1 <= n <= 1000 1 <= nums[i] <= 1000

Explanation

• Create a new array ans with a length twice the length of the input array nums.
  • Populate the first half of ans with the elements of nums.
  • Populate the second half of ans with the elements of nums again, effectively concatenating nums with itself.

• Runtime Complexity: O(n), where n is the length of the input array nums. Storage Complexity: O(n), as we create a new array ans of size 2n.

Code

    def getConcatenation(nums):
    """
    Given an integer array nums of length n, returns an array ans of length 2n where ans[i] == nums[i] and ans[i + n] == nums[i] for 0 <= i < n (0-indexed).

    Args:
        nums (list[int]): An integer array.

    Returns:
        list[int]: The concatenation of two nums arrays.
    """
    n = len(nums)
    ans = [0] * (2 * n)

    for i in range(n):
        ans[i] = nums[i]
        ans[i + n] = nums[i]

    return ans