From cad1020fdf1ce5b784866185c45762c2ed802cd5 Mon Sep 17 00:00:00 2001
From: ivan <ivan1016017@gmail.com>
Date: Tue, 15 Apr 2025 04:23:54 -0600
Subject: [PATCH] adding summary ranges

---
 .../summary_ranges.py                         | 27 +++++++++++++++++++
 .../test_summary_ranges_round_15.py           | 25 +++++++++++++++++
 2 files changed, 52 insertions(+)
 create mode 100644 src/my_project/interviews/top_150_questions_round_15/summary_ranges.py
 create mode 100644 tests/test_150_questions_round_15/test_summary_ranges_round_15.py

diff --git a/src/my_project/interviews/top_150_questions_round_15/summary_ranges.py b/src/my_project/interviews/top_150_questions_round_15/summary_ranges.py
new file mode 100644
index 00000000..08d24dbc
--- /dev/null
+++ b/src/my_project/interviews/top_150_questions_round_15/summary_ranges.py
@@ -0,0 +1,27 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+class Solution:
+    def summaryRanges(self, nums: List[int]) -> List[str]:
+
+        len_nums = len(nums)
+
+        if len_nums == 0: 
+            return []
+        elif len_nums == 1: 
+            return [f'{nums[0]}']
+        else:
+            answer = list()
+            pre = start = nums[0]
+
+            for i in nums[1:]:
+                if i - pre > 1: 
+                    answer.append(f'{start}->{pre}' if pre-start > 0 else
+                                  f'{start}')
+                    start = i 
+                pre = i
+
+            answer.append(f'{start}->{pre}' if pre-start > 0 else f'{start}')
+
+            return answer
+
diff --git a/tests/test_150_questions_round_15/test_summary_ranges_round_15.py b/tests/test_150_questions_round_15/test_summary_ranges_round_15.py
new file mode 100644
index 00000000..398bbb42
--- /dev/null
+++ b/tests/test_150_questions_round_15/test_summary_ranges_round_15.py
@@ -0,0 +1,25 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_15\
+.summary_ranges import Solution
+
+class SummaryRangesTestCase(unittest.TestCase):
+
+    def test_empty(self):
+        solution = Solution()
+        output = solution.summaryRanges(nums=[])
+        target = []
+        self.assertEqual(target, output)
+
+    def test_single_element(self):
+        solution = Solution()
+        output = solution.summaryRanges(nums=[1])
+        target = ['1']
+        self.assertEqual(target, output)
+
+    def test_several_elements(self):
+        solution = Solution()
+        output = solution.summaryRanges(nums=[0,1,2,4,5,7])
+        target = ["0->2","4->5","7"]
+        for k, v in enumerate(target):
+            self.assertEqual(v, output[k])  
+