"""
Rotate an array of n elements to the right by k steps.
For example, with n = 7 and k = 3,
the array [1,2,3,4,5,6,7] is rotated to [5,6,7,1,2,3,4].
Note:
Try to come up as many solutions as you can,
there are at least 3 different ways to solve this problem.
"""
def rotate(nums, k):
"""
:type nums: List[int]
:type k: int
:rtype: void Do not return anything, modify nums in-place instead.
"""
n = len(nums)
k = k % n
reverse(nums, 0, n - k - 1)
reverse(nums, n - k, n - 1)
reverse(nums, 0, n - 1)
def reverse(array, a, b):
while a < b:
array[a], array[b] = array[b], array[a]
a += 1
b -= 1