Introduction

In this blog post, we will explore how to solve the LeetCode problem "3095" 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

You are given an array nums of non-negative integers and an integer k. An array is called special if the bitwise OR of all of its elements is at least k. Return the length of the shortest special non-empty subarray of nums, or return -1 if no special subarray exists. Example 1: Input: nums = [1,2,3], k = 2 Output: 1 Explanation: The subarray [3] has OR value of 3. Hence, we return 1. Note that [2] is also a special subarray. Example 2: Input: nums = [2,1,8], k = 10 Output: 3 Explanation: The subarray [2,1,8] has OR value of 11. Hence, we return 3. Example 3: Input: nums = [1,2], k = 0 Output: 1 Explanation: The subarray [1] has OR value of 1. Hence, we return 1. Constraints: 1 <= nums.length <= 50 0 <= nums[i] <= 50 0 <= k < 64

Explanation

Here's the breakdown of the solution:

• Sliding Window: Use a sliding window approach to efficiently explore all possible subarrays.
• Bitwise OR Calculation: Maintain a running bitwise OR of the elements within the current window.

• Shortest Length Tracking: Keep track of the shortest special subarray found so far.

• Runtime Complexity: O(n), where n is the length of the input array. Storage Complexity: O(1).

Code

    def shortest_special_subarray(nums, k):
    """
    Finds the length of the shortest special non-empty subarray of nums.

    Args:
        nums: A list of non-negative integers.
        k: An integer.

    Returns:
        The length of the shortest special non-empty subarray, or -1 if none exists.
    """

    n = len(nums)
    min_len = float('inf')
    for i in range(n):
        current_or = 0
        for j in range(i, n):
            current_or |= nums[j]
            if current_or >= k:
                min_len = min(min_len, j - i + 1)
                break  # No need to continue extending this subarray
    return min_len if min_len != float('inf') else -1