# 189. Rotate Array
"""
given an integer array 'nums', rotate the array to the right by 'k' stops,
where 'k' is non-negative.
"""
class Solution(object):
def reverse(self, nums, start, end):
while start < end:
tmp = nums[start]
nums[start] = nums[end]
nums[end] = tmp
start += 1
end -= 1
def rotate(self, nums, k):
"""
:type nums: List[int]
:type k: int
:rtype: None Do not return anything, modify nums in-place instead.
"""
n = len(nums)
k %= n
if k < 0:
k += n
self.reverse(nums, 0, n - k - 1)
self.reverse(nums, n - k, n - 1)
self.reverse(nums, 0, n - 1)
if __name__ == "__main__":
obj = Solution()
n1 = [1, 2, 3, 4, 5, 6, 7]
n2 = [-1, -100, 3, 99]
obj.rotate(n1, k=3)
obj.rotate(n2, k=2)
print(n1)
print(n2)
