BinarySearch 0127 Swap Consecutive Index Pairs

Problem statement

https://binarysearch.com/problems/Swap-Consecutive-Index-Pairs/

Solution

Just do what is asked in loop.

Complexity

It is O(n) for time and O(1) for additional space.

Code

class Solution:
    def solve(self, nums):
        n = len(nums)
        for i in range(n//4 + 1):
            if 4*i + 2 < n:
                nums[4*i], nums[4*i+2] = nums[4*i+2], nums[4*i]
            if 4*i + 3 < n:
                nums[4*i+1], nums[4*i+3] = nums[4*i+3], nums[4*i+1]
        return nums