Introduction

In this blog post, we will explore how to solve the LeetCode problem "2733" 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 containing distinct positive integers, find and return any number from the array that is neither the minimum nor the maximum value in the array, or -1 if there is no such number. Return the selected integer. Example 1: Input: nums = [3,2,1,4] Output: 2 Explanation: In this example, the minimum value is 1 and the maximum value is 4. Therefore, either 2 or 3 can be valid answers. Example 2: Input: nums = [1,2] Output: -1 Explanation: Since there is no number in nums that is neither the maximum nor the minimum, we cannot select a number that satisfies the given condition. Therefore, there is no answer. Example 3: Input: nums = [2,1,3] Output: 2 Explanation: Since 2 is neither the maximum nor the minimum value in nums, it is the only valid answer. Constraints: 1 <= nums.length <= 100 1 <= nums[i] <= 100 All values in nums are distinct

Explanation

Here's the breakdown of the solution:

• Early Exit: If the array has fewer than 3 elements, it's impossible to have a number that's neither the minimum nor the maximum. Return -1 immediately.
• Direct Check: Iterate through the array. For each number, check if it's not the minimum and not the maximum of the entire array. If such a number is found, return it immediately. This avoids unnecessary sorting or complex calculations.

• Default Return: If the loop completes without finding a suitable number, it means all numbers are either the minimum or the maximum, so return -1.

• Runtime Complexity: O(n), where n is the length of the array, due to iterating through the array once.

• Storage Complexity: O(1), as we only use a constant amount of extra space.

Code

    def findNonMinOrMax(nums):
    """
    Finds and returns any number from the array that is neither the minimum nor the maximum value in the array, or -1 if there is no such number.

    Args:
        nums: An integer array containing distinct positive integers.

    Returns:
        The selected integer, or -1 if there is no such number.
    """

    n = len(nums)
    if n < 3:
        return -1

    min_val = min(nums)
    max_val = max(nums)

    for num in nums:
        if num != min_val and num != max_val:
            return num

    return -1