Find Maximum Sum of Contiguous Subarray Length k

Q: Find Maximum Sum of Contiguous Subarray Length k

This question evaluates skill in array manipulation and computing aggregate metrics over fixed-length intervals, along with understanding of algorithmic complexity and trade-offs between runtime and memory.

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Use PracHub's coding console to write, test, and debug your solutions in Python or JavaScript. View hints, test against sample inputs, and compare with official solutions.

Q: What difficulty level is this coding question?

This is a Medium difficulty Coding & Algorithms question, commonly asked during Technical Screen rounds at Apple.

Q: What role is this question designed for?

This question is commonly asked for Data Scientist candidates at Apple during technical interviews.

Question

##### Scenario

Monitoring website traffic and needing the highest traffic within any fixed-length time window.

##### Question

Given an array of positive integers representing hits per minute and an integer k, return the maximum sum of any contiguous subarray of length k. Provide time and space complexity.

##### Hints

Two-pointer sliding window keeps running sum; O(n) time, O(
1) space.

PracHub · Accepted Answer

from typing import List def max_sum_subarray_k(nums: List[int], k: int) -> int: n = len(nums) # Assumes 1 <= k <= n curr = sum(nums[:k]) max_sum = curr for i in range(k, n): curr += nums[i] - nums[i - k] if curr > max_sum: max_sum = curr return max_sum Use a sliding window of size k. Initialize the sum of the first k elements. For each subsequent position, add the entering element and subtract the leaving element to update the running sum in O(1). Keep track of the maximum running sum encountered.

Quick Overview

Find Maximum Sum of Contiguous Subarray Length k

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