public class Solution {
    /**
     * @param nums a list of integer
     * @return void
     */
    public void wiggleSort(int[] nums) {
        for(int i=1; i<nums.length; i++){
            if ((i%2==1 && nums[i-1]>nums[i])||
            (i%2==0 && nums[i-1]<nums[i]))
                swap(nums, i-1, i);
        }

    }

    /**
     * Swap two values
     * */
    public void swap(int[] nums, int i, int j) {
        int temp = nums[i];
        nums[i] = nums[j];
        nums[j] = temp;
    }

}