Rotate Array

Problem Description

Given an integer array nums, rotate the array to the right by k steps, where k is non-negative.

Examples

Example 1:

• Input: nums = [1,2,3,4,5,6,7], k = 3
• Output: [5,6,7,1,2,3,4]
• Explanation:
  • Rotate 1 step to the right: [7,1,2,3,4,5,6]
  • Rotate 2 steps to the right: [6,7,1,2,3,4,5]
  • Rotate 3 steps to the right: [5,6,7,1,2,3,4]

Example 2:

• Input: nums = [-1,-100,3,99], k = 2
• Output: [3,99,-1,-100]
• Explanation:
  • Rotate 1 step to the right: [99,-1,-100,3]
  • Rotate 2 steps to the right: [3,99,-1,-100]

Constraints

• 1 <= nums.length <= 10^5
• -2^{31} <= nums[i] <= 2^{31} - 1
• 0 <= k <= 10^5

Follow Up

• Try to come up with as many solutions as you can. There are at least three different ways to solve this problem.
• Could you do it in-place with O(1) extra space?

Code Template

class Solution:
    def rotate(self, nums: List[int], k: int) -> None:
        """
        Do not return anything, modify nums in-place instead.
        """
        # Write your code here
        pass

Solutions

• Solution 1: This approach uses the reverse method to rotate the array in-place with O(1) extra space.

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