324. Wiggle Sort II
Given an unsorted array nums, reorder it such that nums[0] < nums[1] > nums[2] < nums[3]....
Example 1:
Input: nums = [1, 5, 1, 1, 6, 4]
Output: One possible answer is [1, 4, 1, 5, 1, 6].
Example 2:
Input: nums = [1, 3, 2, 2, 3, 1]
Output: One possible answer is [2, 3, 1, 3, 1, 2].
Note:
You may assume all input has valid answer.
Follow Up:
Can you do it in O(n) time and/or in-place with O(1) extra space?
public void wiggleSort(int[] nums) {
Arrays.sort(nums);
int[] result = new int[nums.length];
int cnt = 0;
for(int i = (result.length-1) % 2 == 1 ? result.length-2 : result.length-1; i >= 0; i -= 2) {
result[i] = nums[cnt++];
}
for(int i = (result.length-1) % 2 == 0 ? result.length-2 : result.length-1; i >= 0; i -= 2) {
result[i] = nums[cnt++];
}
System.arraycopy(result, 0, nums, 0, nums.length);
}