Check if Array Is Sorted and Rotated

EasyArrays & Hashingsimulation

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

Given an integer array nums, return true if it can be produced by taking some array sorted in non-decreasing order and rotating it by some number of positions (zero included), and false otherwise. Rotating by r moves the last r elements to the front while keeping their order. The array may contain duplicates.

Examples

Input: nums = [3,4,5,1,2]
Output: true
[1,2,3,4,5] rotated so it starts at 3.
Input: nums = [2,1,3,4]
Output: false
No rotation of this array is sorted.
Input: nums = [1,2,3]
Output: true
A rotation by 0 positions is allowed.

Constraints

  • 1 <= nums.length <= 100
  • 1 <= nums[i] <= 100 (tests may also include negatives)

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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