# Solving Leetcode Interviews in Seconds with AI: Maximum and Minimum Sums of at Most Size K Subarrays


	# Introduction
	In this blog post, we will explore how to solve the LeetCode problem "3430" using AI. LeetCode is a popular platform for preparing for coding interviews, and with the help of AI tools like [Chatmagic](https://www.chatmagic.app), 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 integer array nums and a positive integer k. Return the sum of the maximum and minimum elements of all subarrays with at most k elements.   Example 1:  Input: nums = [1,2,3], k = 2 Output: 20 Explanation: The subarrays of nums with at most 2 elements are:    Subarray Minimum Maximum Sum   [1] 1 1 2   [2] 2 2 4   [3] 3 3 6   [1, 2] 1 2 3   [2, 3] 2 3 5   Final Total     20    The output would be 20.  Example 2:  Input: nums = [1,-3,1], k = 2 Output: -6 Explanation: The subarrays of nums with at most 2 elements are:    Subarray Minimum Maximum Sum   [1] 1 1 2   [-3] -3 -3 -6   [1] 1 1 2   [1, -3] -3 1 -2   [-3, 1] -3 1 -2   Final Total     -6    The output would be -6.    Constraints:  1 <= nums.length <= 80000 1 <= k <= nums.length -106 <= nums[i] <= 106  

	# Explanation
	Here's the solution:

*   Iterate through all possible subarrays of `nums` with length at most `k`.
*   For each subarray, find the minimum and maximum elements.
*   Add the sum of the minimum and maximum to the running total.

*   Time Complexity: O(n\*k), Space Complexity: O(1)

	
	# Code
	```python
	def sub_array_max_min(nums, k):
    """
    Calculates the sum of the maximum and minimum elements of all subarrays with at most k elements.

    Args:
        nums (list[int]): An integer array.
        k (int): A positive integer representing the maximum length of subarrays.

    Returns:
        int: The sum of the maximum and minimum elements of all subarrays with at most k elements.
    """

    total_sum = 0
    n = len(nums)

    for i in range(n):
        for j in range(i, min(i + k, n)):
            sub_array = nums[i : j+1]
            min_val = min(sub_array)
            max_val = max(sub_array)
            total_sum += min_val + max_val

    return total_sum
	```