feat(work): add solution for LeetCode 189 Rotate Array

work/1/Medium/Array/189.rotate-array.py

@@ -0,0 +1,64 @@
+"""
+189. Rotate Array
+Difficulty: Medium
+https://leetcode.com/problems/rotate-array/
+
+──────────────────────────────────────────────────
+
+Given an integer array nums, rotate the array to the right by k
+steps, where k is non-negative.
+
+
+
+Example 1:
+
+Input: nums = [1,2,3,4,5,6,7], 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: nums = [-1,-100,3,99], 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]
+
+
+
+Constraints:
+
+        • 1 <= nums.length <= 10^5
+
+        • -2^31 <= nums[i] <= 2^31 - 1
+
+        • 0 <= k <= 10^5
+
+
+
+Follow up:
+
+• Try to come up with as many solutions as you can. There are at
+least three different ways to solve this problem.
+
+        • Could you do it in-place with O(1) extra space?
+"""
+
+
+class Solution:
+    def rotate(self, nums: list[int], k: int) -> None:
+        N = len(nums) - 1
+        cut = k % len(nums)
+
+        def reverse(l, r):
+            while l <= r:
+                nums[l], nums[r] = nums[r], nums[l]
+                l += 1
+                r -= 1
+
+        reverse(0, N)
+        reverse(0, cut - 1)
+        reverse(cut, N)