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