Introduction

In this blog post, we will explore how to solve the LeetCode problem "78" 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 unique elements, return all possible subsets (the power set). The solution set must not contain duplicate subsets. Return the solution in any order. Example 1: Input: nums = [1,2,3] Output: [[],[1],[2],[1,2],[3],[1,3],[2,3],[1,2,3]] Example 2: Input: nums = [0] Output: [[],[0]] Constraints: 1 <= nums.length <= 10 -10 <= nums[i] <= 10 All the numbers of nums are unique.

Explanation

• Iterative Approach: Generate subsets iteratively. Start with an empty set. For each number in the input array, create new subsets by adding the number to all existing subsets.
  • Avoid Duplicates: Since the input array contains unique elements, adding each element to the existing subsets will inherently avoid duplicate subsets.
  • Build Subsets Incrementally: Build the subsets incrementally by processing each element of the input array.

• Time Complexity: O(N * 2^N), where N is the number of elements in the input array.
• Space Complexity: O(N * 2^N) to store the power set.

Code

    def subsets(nums):
    """
    Generates all possible subsets (the power set) of a given integer array.

    Args:
        nums: An integer array of unique elements.

    Returns:
        A list of lists representing all possible subsets of nums.
    """

    result = [[]]  # Start with an empty set
    for num in nums:
        new_subsets = []
        for subset in result:
            new_subsets.append(subset + [num])  # Add current number to existing subsets
        result.extend(new_subsets)  # Add newly created subsets to the result
    return result