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Python - Rotate elements of an array by n places in the most efficient way

Given an array, rotate the array to the right by k steps, where k is non-negative.
Example 1:
Input: [1,2,3,4,5,6,7] and k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps to the right: [7,1,2,3,4,5,6]
rotate 2 steps to the right: [6,7,1,2,3,4,5]
rotate 3 steps to the right: [5,6,7,1,2,3,4]
Example 2:
Input: [-1,-100,3,99] and k = 2
Output: [3,99,-1,-100]
Explanation: 
rotate 1 steps to the right: [99,-1,-100,3]
rotate 2 steps to the right: [3,99,-1,-100]
Note:
  • Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem.
  • Could you do it in-place with O(1) extra space?

Solution 1

class Solution:
def rotate(self, nums, k):
print(nums)
for i in range(0, k):
nums.insert(0, nums[-1])
nums.pop(-1)
return nums


obj = Solution()
print(obj.rotate([1,2,3,4,5,6,7], 3))

OUTPUT

[1, 2, 3, 4, 5, 6, 7]
[5, 6, 7, 1, 2, 3, 4]

BIG O

O(n)

Solution 2

class Solution:
def rotate(self, nums, k):
print(nums)
nums2 = nums[-k:]
nums = list(set(nums).difference(set(nums2)))
nums2.extend(nums)
return nums2


obj = Solution()
print(obj.rotate([1,2,3,4,5,6,7], 3))

OUTPUT

[1, 2, 3, 4, 5, 6, 7]
[5, 6, 7, 1, 2, 3, 4]

BIG O

O(1)

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