D. J.:

- Added leetcode problem and solution for 189 Rotate Array

Author: nobodyPerfecZ

README.md

@@ -11,6 +11,7 @@ This repository contains awesome LeetCode problems and solutions written in Pyth
 - [121 Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/description/)
 - [122 Best Time to Buy and Sell Stock II](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/description/)
 - [169 Majority Element](https://leetcode.com/problems/majority-element/description/)
+- [189 Rotate Array](https://leetcode.com/problems/rotate-array/description/)
 
 ## Development 🔧
 

awesome_python_leetcode/_189_rotate_array.py

@@ -0,0 +1,19 @@
+from typing import List
+
+
+class Solution:
+    def rotate(self, nums: List[int], k: int) -> None:
+        """
+        Given an integer array nums, rotate the array to the right by k steps, where k is non-negative.
+        """
+
+        def rev(left: int, right: int):
+            while left < right:
+                nums[left], nums[right] = nums[right], nums[left]
+                left += 1
+                right -= 1
+
+        k = k % len(nums)
+        rev(0, len(nums) - 1)
+        rev(0, k - 1)
+        rev(k, len(nums) - 1)

tests/test_189_rotate_array.py

@@ -0,0 +1,17 @@
+from typing import List
+
+import pytest
+
+from awesome_python_leetcode._189_rotate_array import Solution
+
+
+@pytest.mark.parametrize(
+    argnames=["nums", "k", "expected"],
+    argvalues=[
+        ([1, 2, 3, 4, 5, 6, 7], 3, [5, 6, 7, 1, 2, 3, 4]),
+        ([-1, -100, 3, 99], 2, [3, 99, -1, -100]),
+    ],
+)
+def test_func(nums: List[int], k: int, expected: int):
+    Solution().rotate(nums, k)
+    assert nums == expected