wiggle-sort.js

/**
 * Wiggle Sort
 *
 * Given an unsorted array nums, reorder it in-place such that nums[0] <= nums[1] >= nums[2] <= nums[3]....
 *
 * For example, given nums = [3, 5, 2, 1, 6, 4], one possible answer is [1, 6, 2, 5, 3, 4].
 */

/**
 * @param {number[]} nums
 * @return {void} Do not return anything, modify nums in-place instead.
 */
const wiggleSort = nums => {
  for (let i = 1; i < nums.length; i++) {
    if ((i % 2 === 0) === nums[i] > nums[i - 1]) {
      [nums[i], nums[i - 1]] = [nums[i - 1], nums[i]];
    }
  }
};