Largest Element in an Array after Merge Operations — LeetCode 2789 Python Solution

The problem

You are given a 0-indexed array nums consisting of positive integers. You can do the following operation on the array any number of times: Choose an index i such that 0 <= i < nums.length - 1 and nums[i] <= nums[i + 1].

Example

Input

nums = [2,3,7,9,3]

Output

21

Explanation

We can apply the following operations on the array:

Python solution

class Solution:
    def maxArrayValue(self, nums: List[int]) -> int:
        for i in range(len(nums) - 2, -1, -1):
            if nums[i] <= nums[i + 1]:
                nums[i] += nums[i + 1]
        return max(nums)

Complexity

Pattern: Greedy

Take the locally best option every time — when you can prove that never costs you later. LeetCode 2789. Largest Element in an Array after Merge Operations is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Greedy.

The greedy guide has the Python template for the pattern and the 346 LeetCode problems that use it.

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