1 public class Solution { 2     public void wiggleSort(int[] nums) { 3         Arrays.sort(nums); 4          5         int[] result = new int[nums.length]; 6         int bound = nums.length % 2 == 1 ? nums.length / 2 : nums.length / 2 - 1; 7         int i = bound; 8         int j = nums.length - 1; 9         int index = 0;10         11         while (index < nums.length) {12             result[index++] = nums[i--];13             if (j > bound) {14                 result[index++] = nums[j--];15             }16         }17         18         for (i = 0; i < nums.length; i++) {19             nums[i] = result[i];20         }21     }22 }

1. Use backward arrangement in case of [4, 5, 5, 6].