Introduction

In this blog post, we will explore how to solve the LeetCode problem "1300" 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 arr and a target value target, return the integer value such that when we change all the integers larger than value in the given array to be equal to value, the sum of the array gets as close as possible (in absolute difference) to target. In case of a tie, return the minimum such integer. Notice that the answer is not neccesarilly a number from arr. Example 1: Input: arr = [4,9,3], target = 10 Output: 3 Explanation: When using 3 arr converts to [3, 3, 3] which sums 9 and that's the optimal answer. Example 2: Input: arr = [2,3,5], target = 10 Output: 5 Example 3: Input: arr = [60864,25176,27249,21296,20204], target = 56803 Output: 11361 Constraints: 1 <= arr.length <= 104 1 <= arr[i], target <= 105

Explanation

Here's an efficient solution to the problem:

• Binary Search: Utilize binary search to find the optimal value. The search space is from 0 to the maximum element in the array.
• Calculate Sum: For each value considered in the binary search, calculate the sum of the modified array (where elements greater than the value are replaced with the value).

• Minimize Difference: Track the value that yields the smallest absolute difference between the modified sum and the target. Handle ties by selecting the smaller value.

• Runtime Complexity: O(N log M), where N is the length of the array and M is the maximum element in the array. Storage Complexity: O(1).

Code

    def findBestValue(arr: list[int], target: int) -> int:
    """
    Given an integer array arr and a target value target, return the integer value
    such that when we change all the integers larger than value in the given array
    to be equal to value, the sum of the array gets as close as possible (in absolute
    difference) to target.

    In case of a tie, return the minimum such integer.
    Notice that the answer is not neccesarilly a number from arr.

    For example:
    findBestValue([4,9,3], 10) == 3
    findBestValue([2,3,5], 10) == 5
    findBestValue([60864,25176,27249,21296,20204], 56803) == 11361
    """
    arr.sort()
    n = len(arr)
    left, right = 0, arr[-1]
    best_value = 0
    min_diff = float('inf')

    while left <= right:
        mid = (left + right) // 2
        current_sum = 0
        for num in arr:
            current_sum += min(num, mid)

        diff = abs(current_sum - target)

        if diff < min_diff:
            min_diff = diff
            best_value = mid
        elif diff == min_diff and mid < best_value:
            best_value = mid

        if current_sum < target:
            left = mid + 1
        else:
            right = mid - 1

    return best_value