[LeetCode] 280. Wiggle Sort

Problem

Given an unsorted array nums, reorder it in-place such that nums[0] <= nums[1] >= nums[2] <= nums[3]....

Example:

Input: nums = [3,5,2,1,6,4]
Output: One possible answer is [3,5,1,6,2,4]

Solution

class Solution {
    public void wiggleSort(int[] nums) {
        for (int i = 0; i < nums.length; i++) {
            if (i%2 == 1) {
                if (nums[i] < nums[i-1]) swap(nums, i, i-1);
            } else {
                if (i != 0 && nums[i] > nums[i-1]) swap(nums, i, i-1);
            }
        }
    }
    private void swap(int[] nums, int i, int j) {
        int temp = nums[i];
        nums[i] = nums[j];
        nums[j] = temp;
    }
}