280. Wiggle Sort

• Difficulty: Medium

• Topics: Array, Sort

• Similar Questions:

  • Sort Colors

  • Wiggle Sort II

Problem:

Given an unsorted array nums, reorder it in-place such that nums[0] <= nums[1] >= nums[2] <= nums[3]....

Example:

Input: nums = [3,5,2,1,6,4]
Output: One possible answer is [3,5,1,6,2,4]

Solutions:

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