#2789

Largest Element in an Array after Merge Operations

Medium
ArrayGreedyGreedyArray
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Approaches

Brute ForceOptimal
Complexity Comparison
Brute ForceOptimal Solution
Time
O(n²)
O(n)
Space
O(1)
O(1)
💡

Intuition

Time O(n)Space O(1)

The optimal approach involves iterating through the array from the end to the beginning, merging elements as we go. This allows us to efficiently combine elements while keeping track of the maximum value without needing to repeatedly traverse the array.

⚙️

Algorithm

5 steps
  1. 1Step 1: Initialize a variable to store the current maximum element as the last element of the array.
  2. 2Step 2: Iterate through the array from the second last element to the first element.
  3. 3Step 3: For each element, if it is less than or equal to the current maximum, merge it into the current maximum.
  4. 4Step 4: Update the current maximum accordingly.
  5. 5Step 5: Return the current maximum after the loop.
solution.py8 lines
1# Full working Python code
2
3def largestElement(nums):
4    max_elem = nums[-1]
5    for i in range(len(nums) - 2, -1, -1):
6        if nums[i] <= max_elem:
7            max_elem += nums[i]
8    return max_elem

Complexity note: The time complexity is O(n) since we only make a single pass through the array. The space complexity is O(1) because we are using a constant amount of extra space.

  • 1Merging elements increases the maximum value.
  • 2Processing from the end allows for efficient accumulation.

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