rotate-array.js

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

 

Example 1:

Input: nums = [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps 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 steps to the right: [99,-1,-100,3]
rotate 2 steps to the right: [3,99,-1,-100]

*/

var rotate = function (nums, k) {
    let l = 0
    let r = nums.length - 1
    k = k % nums.length

    while (l < r) {
        [nums[l], nums[r]] = [nums[r], nums[l]]
        l += 1
        r -= 1
    }

    l = 0
    r = k - 1
    while (l < r) {
        [nums[l], nums[r]] = [nums[r], nums[l]]
        l += 1
        r -= 1
    }

    l = k
    r = nums.length - 1
    while (l < r) {
        [nums[l], nums[r]] = [nums[r], nums[l]]
        l += 1
        r -= 1
    }
};i