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].

sort the array, then swap each two adjacent elements.

class Solution {
public:
    void wiggleSort(vector<int>& nums) {
        sort(nums.begin(), nums.end());
        for(size_t i = 1; i + 1 < nums.size(); i += 2){
            swap(nums[i], nums[i + 1]);
        }
    }
};