Leetcode 280: Wiggle Sort

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].

 

public class Solution {
    public void WiggleSort(int[] nums) {
        if (nums == null || nums.Length < 2) return;
        
        for (int i = 1; i < nums.Length; i++)
        {
            if (i % 2 == 1 && nums[i - 1] > nums[i])
            {
                var tmp = nums[i - 1];
                nums[i - 1] = nums[i];
                nums[i] = tmp;
            }
            
            if (i % 2 == 0 && nums[i] > nums[i - 1])
            {
                var tmp = nums[i - 1];
                nums[i - 1] = nums[i];
                nums[i] = tmp;
            }
        }
    }
}