How hard is LeetCode 2208. Minimum Operations to Halve Array Sum?

LeetCode 2208. Minimum Operations to Halve Array Sum is rated Medium on LeetCode.

What is the time complexity of LeetCode 2208. Minimum Operations to Halve Array Sum?

The Python solution on this page runs in O(n \times \log n).

What is the space complexity of LeetCode 2208. Minimum Operations to Halve Array Sum?

The Python solution on this page uses O(n) auxiliary space.

What topics does LeetCode 2208. Minimum Operations to Halve Array Sum cover?

LeetCode 2208. Minimum Operations to Halve Array Sum is tagged Greedy, Array and Heap (Priority Queue) on LeetCode.

Minimum Operations to Halve Array Sum — LeetCode 2208 Python Solution

MediumGreedyArrayHeap (Priority Queue)

Problem: #2208
Pattern: Heap / Priority Queue
Reading time: 3 min
Source: leetcode.com

The problem

You are given an array nums of positive integers. In one operation, you can choose any number from nums and reduce it to exactly half the number.

Example

Input: nums = [5,19,8,1]
Output: 3
Explanation: The initial sum of nums is equal to 5 + 19 + 8 + 1 = 33.

Python solution

Python

class Solution:
    def halveArray(self, nums: List[int]) -> int:
        s = sum(nums) / 2
        pq = []
        for x in nums:
            heappush(pq, -x)
        ans = 0
        while s > 0:
            t = -heappop(pq) / 2
            s -= t
            heappush(pq, -t)
            ans += 1
        return ans

Complexity

Measure	Complexity
Time	O(n \times \log n)
Space	O(n) auxiliary

Pattern: Heap / Priority Queue

Keep only the best k elements, or always pull the smallest, in log time. LeetCode 2208. Minimum Operations to Halve Array Sum is filed here because LeetCode tags it Heap (Priority Queue), which is the vocabulary this hub collects.

The heap / priority queue guide has the Python template for the pattern and the 163 LeetCode problems that use it.

Frequently asked questions

How hard is LeetCode 2208. Minimum Operations to Halve Array Sum?: LeetCode 2208. Minimum Operations to Halve Array Sum is rated Medium on LeetCode.
What is the time complexity of LeetCode 2208. Minimum Operations to Halve Array Sum?: The Python solution on this page runs in O(n \times \log n).
What is the space complexity of LeetCode 2208. Minimum Operations to Halve Array Sum?: The Python solution on this page uses O(n) auxiliary space.
What topics does LeetCode 2208. Minimum Operations to Halve Array Sum cover?: LeetCode 2208. Minimum Operations to Halve Array Sum is tagged Greedy, Array and Heap (Priority Queue) on LeetCode.