lintcode-508. Wiggle Sort

Given an unsorted array nums, reorder it in-place such that nums[0] <= nums[1] >= nums[2] <= nums[3].... Example Example 1: Input: [3, 5, 2, 1, 6, 4] Output: [1, 6, 2, 5, 3, 4] Explanation: This question may have multiple answers, and [2, 6, 1, 5, 3, 4] is also ok. Example 2: Input: [1, 2, 3, 4] Output: [2, 1, 4, 3]

从左到右 扫一遍，如果不满足条件就交换

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