D. J.:

- Added the leetcode problem and solution for 228 Summary Ranges

Author: nobodyPerfecZ

README.md

@@ -42,6 +42,7 @@ This repository contains awesome LeetCode problems and solutions written in Pyth
 - [202 Happy Number](https://leetcode.com/problems/happy-number/description/)
 - [205 Isomorphic Strings](https://leetcode.com/problems/isomorphic-strings/description/)
 - [219 Contains Duplicates II](https://leetcode.com/problems/contains-duplicate-ii/description/)
+- [228 Summary Ranges](https://leetcode.com/problems/summary-ranges/description/)
 - [242 Valid Anagram](https://leetcode.com/problems/valid-anagram/description/)
 - [290 Word Pattern](https://leetcode.com/problems/word-pattern/description/)
 - [383 Ransom Note](https://leetcode.com/problems/ransom-note/description/)

awesome_python_leetcode/_228_summary_ranges.py

@@ -0,0 +1,31 @@
+from typing import List
+
+
+class Solution:
+    def summaryRanges(self, nums: List[int]) -> List[str]:
+        """
+        You are given a sorted unique integer array nums.
+
+        A range [a,b] is the set of all integers from a to b (inclusive).
+
+        Return the smallest sorted list of ranges that cover all the numbers in the array exactly.
+        That is, each element of nums is covered by exactly one of the ranges, and there is no
+        integer x such that x is in one of the ranges but not in nums.
+
+        Each range [a,b] in the list should be output as:
+        - "a->b" if a != b
+        - "a" if a == b
+        """
+        ranges = []
+        for left, n in enumerate(nums):
+            if n - 1 not in nums:
+                length = 0
+                right = left
+                while (n + length) in nums:
+                    length += 1
+                    right += 1
+                if left == right - 1:
+                    ranges.append(f"{nums[left]}")
+                else:
+                    ranges.append(f"{nums[left]}->{nums[right-1]}")
+        return ranges

tests/test_228_summary_ranges.py

@@ -0,0 +1,17 @@
+from typing import List
+
+import pytest
+
+from awesome_python_leetcode._228_summary_ranges import Solution
+
+
+@pytest.mark.parametrize(
+    argnames=["nums", "expected"],
+    argvalues=[
+        ([0, 1, 2, 4, 5, 7], ["0->2", "4->5", "7"]),
+        ([0, 2, 3, 4, 6, 8, 9], ["0", "2->4", "6", "8->9"]),
+    ],
+)
+def test_func(nums: List[int], expected: List[str]):
+    ranges = Solution().summaryRanges(nums)
+    assert ranges == expected