280. Wiggle Sort

    /*
     * 280. Wiggle Sort
     * 2016-6-27 by Mingyang
     * Given an unsorted array nums, reorder it in-place such that nums[0] <= nums[1] >= nums[2] <= nums[3]....
     * 对于题目的理解要准确！就是奇数位上的数字要大于等于周边的，那么我只用看小于的情况就交换好了
     */
     public void wiggleSort(int[] nums) {
            for(int i=0;i<nums.length;i++)
                if(i%2==1){
                   if(nums[i-1]>nums[i]) swap(nums, i);
                }else if(i!=0 && nums[i-1]<nums[i]) swap(nums, i);
        }
        public void swap(int[] nums, int i){
              int tmp=nums[i];
              nums[i]=nums[i-1];
              nums[i-1]=tmp;
        }