D. J.:

- Added the leetcode problem and solution for 89 and 717

Author: nobodyPerfecZ

README.md

@@ -133,6 +133,7 @@
 - [82 Remove Duplicates from Sorted List II](https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/description/)
 - [86 Partition List](https://leetcode.com/problems/partition-list/description/)
 - [88 Merge Sorted Array](https://leetcode.com/problems/merge-sorted-array/description/)
+- [89 Gray Code](https://leetcode.com/problems/gray-code/description/)
 - [91 Decode Ways](https://leetcode.com/problems/decode-ways/description/)
 - [92 Reverse Linked List II](https://leetcode.com/problems/reverse-linked-list-ii/description/)
 - [95 Unique Binary Search Trees II](https://leetcode.com/problems/unique-binary-search-trees-ii/description/)
@@ -254,6 +255,7 @@
 - [673 Number of Longest Increasing Subsequence](https://leetcode.com/problems/number-of-longest-increasing-subsequence/description/)
 - [712 Minimum ASCII Delete Sum for Two Strings](https://leetcode.com/problems/minimum-ascii-delete-sum-for-two-strings/description/)
 - [714 Best Time to Buy and Sell Stock with Transaction Fee](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-transaction-fee/description/)
+- [717 1-bit and 2-bit Characters](https://leetcode.com/problems/1-bit-and-2-bit-characters/description/)
 - [724 Find Pivot Index](https://leetcode.com/problems/find-pivot-index/description/)
 - [735 Asteroid Collision](https://leetcode.com/problems/asteroid-collision/description/)
 - [740 Delete and Earn](https://leetcode.com/problems/delete-and-earn/description/)

awesome_python_leetcode/_717_1_bit_and_2_bit_characters.py

@@ -0,0 +1,23 @@
+from typing import List
+
+
+class Solution:
+    """Base class for all LeetCode Problems."""
+
+    def isOneBitCharacter(self, bits: List[int]) -> bool:
+        """
+        We have two special characters:
+        - The first character can be represented by one bit 0.
+        - The second character can be represented by two bits (10 or 11).
+
+        Given a binary array bits that ends with 0, return true if the last character
+        must be a one-bit character.
+        """
+        i = 0
+        while i < len(bits):
+            if i == len(bits) - 2 and bits[i] == 1:
+                return False
+            if bits[i] == 1:
+                i += 1
+            i += 1
+        return True

awesome_python_leetcode/_89_gray_code.py

@@ -0,0 +1,26 @@
+from typing import List
+
+
+class Solution:
+    """Base class for all LeetCode Problems."""
+
+    def grayCode(self, n: int) -> List[int]:
+        """
+        An n-bit gray code sequence is a sequence of 2n integers where:
+        - Every integer is in the inclusive range [0, 2n - 1],
+        - The first integer is 0,
+        - An integer appears no more than once in the sequence,
+        - The binary representation of every pair of adjacent integers differs by
+        exactly one bit, and
+        - The binary representation of the first and last integers differs by exactly
+        one bit.
+
+        Given an integer n, return any valid n-bit gray code sequence.
+        """
+        result = []
+        total_numbers = 1 << n
+
+        for i in range(total_numbers):
+            result.append(i ^ (i >> 1))
+
+        return result

tests/test_717_1_bit_and_2_bit_characters.py

@@ -0,0 +1,18 @@
+from typing import List
+
+import pytest
+
+from awesome_python_leetcode._717_1_bit_and_2_bit_characters import Solution
+
+
+@pytest.mark.parametrize(
+    argnames=["bits", "expected"],
+    argvalues=[
+        ([1, 0, 0], True),
+        ([1, 1, 1, 0], False),
+    ],
+)
+def test_func(bits: List[int], expected: bool):
+    """Tests the solution of a LeetCode problem."""
+    is_one_bit_character = Solution().isOneBitCharacter(bits)
+    assert is_one_bit_character is expected

tests/test_89_gray_code.py

@@ -0,0 +1,18 @@
+from typing import List
+
+import pytest
+
+from awesome_python_leetcode._89_gray_code import Solution
+
+
+@pytest.mark.parametrize(
+    argnames=["n", "expected"],
+    argvalues=[
+        (2, [0, 1, 3, 2]),
+        (1, [0, 1]),
+    ],
+)
+def test_func(n: int, expected: List[int]):
+    """Tests the solution of a LeetCode problem."""
+    gray_code = Solution().grayCode(n)
+    assert gray_code == expected