Question
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]
Code
class Solution {
public void wiggleSort(int[] nums) {
for(int i=1; i<nums.length; i++) {
if(i%2 == 1 && nums[i] < nums[i-1]) {
swap(nums, i, i-1);
}
else if(i%2 == 0 && nums[i] > nums[i-1]) {
swap(nums, i, i-1);
}
}
}
private void swap(int[] nums, int i1, int i2) {
int t = nums[i1];
nums[i1] = nums[i2];
nums[i2] = t;
}
}
Performance
O(n)