Merge pull request #17 from codewithme-py/feat/contains-duplicate-ii-0219

problem solution & test 0219

Author: codewithme-py

solutions/contains_duplicate_ii_0219.py

@@ -0,0 +1,17 @@
+class Solution:
+    def containsNearbyDuplicate(self, nums: list[int], k: int) -> bool:
+        """
+        Function checks if there are duplicates in the array nums within k.
+        set guarantees O(1) for addition and checking for existence.
+        The size of set never exceeds k+1.
+        Memory O(k)
+        Time O(n)
+        """
+        window_set = set()
+        for i in range(len(nums)):
+            if nums[i] in window_set:
+                return True
+            window_set.add(nums[i])
+            if i >= k:
+                window_set.remove(nums[i - k])
+        return False

tests/test_contains_duplicate_ii_0219.py

@@ -0,0 +1,15 @@
+import pytest
+
+from solutions.contains_duplicate_ii_0219 import Solution
+
+
+@pytest.mark.parametrize('nums, k, expected', [
+    ([1,2,3,1], 3, True),
+    ([1,0,1,1], 1, True),
+    ([1,2,3,1,2,3], 2, False),
+    ([99,99], 2, True),
+    ([1,2,3,4,5,6,7,8,9,10], 3, False),
+])
+def test_solution(nums: list[int], k: int, expected: bool) -> None:
+    sol = Solution()
+    assert sol.containsNearbyDuplicate(nums, k) == expected