Sliding Window Maximum

HardArraysMonotonic Stack

Solve this the way you would in the interview: out loud, on a timer, with an AI interviewer asking follow-ups while you code. You get a scored report at the end.

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Problem

You are given an array of integers nums, there is a sliding window of size k which is moving from the very left of the array to the very right. You can only see the k numbers in the window. Each time the sliding window moves right by one position. Return the max sliding window.

Examples

Input: nums = [1,3,-1,-3,5,3,6,7], k = 3
Output: [3,3,5,5,6,7]
Window [1,3,-1] → max 3; [3,-1,-3] → 3; [-1,-3,5] → 5; [-3,5,3] → 5; [5,3,6] → 6; [3,6,7] → 7.
Input: nums = [1], k = 1
Output: [1]

Constraints

  • 1 <= nums.length <= 10^5
  • -10^4 <= nums[i] <= 10^4
  • 1 <= k <= nums.length

What the interviewer grades

A correct solution is one of five scores. The report also grades problem understanding (did you clarify inputs and edge cases before coding), problem solving, communication while you work, code quality, and testing. See a sample report, or read up on the pattern in the lessons.

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