Introduction

In this blog post, we will explore how to solve the LeetCode problem "1389" 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 two arrays of integers nums and index. Your task is to create target array under the following rules: Initially target array is empty. From left to right read nums[i] and index[i], insert at index index[i] the value nums[i] in target array. Repeat the previous step until there are no elements to read in nums and index. Return the target array. It is guaranteed that the insertion operations will be valid. Example 1: Input: nums = [0,1,2,3,4], index = [0,1,2,2,1] Output: [0,4,1,3,2] Explanation: nums index target 0 0 [0] 1 1 [0,1] 2 2 [0,1,2] 3 2 [0,1,3,2] 4 1 [0,4,1,3,2] Example 2: Input: nums = [1,2,3,4,0], index = [0,1,2,3,0] Output: [0,1,2,3,4] Explanation: nums index target 1 0 [1] 2 1 [1,2] 3 2 [1,2,3] 4 3 [1,2,3,4] 0 0 [0,1,2,3,4] Example 3: Input: nums = [1], index = [0] Output: [1] Constraints: 1 <= nums.length, index.length <= 100 nums.length == index.length 0 <= nums[i] <= 100 0 <= index[i] <= i

Explanation

• List Insertion: The core idea is to iterate through nums and index simultaneously, using the insert() method of Python lists to place nums[i] at the position specified by index[i] in the target list.
  • Iterative Construction: The target list is built incrementally, starting from an empty list, by inserting elements at the appropriate indices in each iteration.

• Runtime & Storage Complexity: The runtime complexity is O(n²) due to the insert operation taking O(n) time in the worst case for each element, where n is the number of elements. The storage complexity is O(n) as we create a new list of size n.

Code

    def create_target_array(nums, index):
    """
    Creates a target array based on the given nums and index arrays.

    Args:
        nums: A list of integers.
        index: A list of integers representing the indices to insert the corresponding nums values.

    Returns:
        A list representing the target array.
    """

    target = []
    for i in range(len(nums)):
        target.insert(index[i], nums[i])
    return target