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].

Solution

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

    public void swap(int[] nums, int i) {
        int tmp = nums[i];
        nums[i] = nums[i - 1];
        nums[i - 1] = tmp;
    }
}