Merge pull request #18 from codewithme-py/feat/contains-duplicate-iii-0220

problem solution & test 0220

Author: codewithme-py

solutions/contains_duplicate_iii_0220.py

@@ -0,0 +1,38 @@
+class Solution:
+    def containsNearbyAlmostDuplicate(
+        self, nums: list[int], indexDiff: int, valueDiff: int
+        ) -> bool:
+        """
+        Look for two different indices i and j, where:
+        1. |i - j| <= indexDiff  (indices are close)
+        2. |nums[i] - nums[j]| <= valueDiff  (values are close)
+        Args:
+            nums (list[int]): Input array.
+            indexDiff (int): Maximum distance between indices.
+            valueDiff (int): Maximum distance between values.
+        Returns:
+            bool: True, if a suitable pair of indices is found, otherwise False.
+        Time Complexity:
+            O(n) — each element is processed once,
+            checking 3 buckets = O(1).
+        Space Complexity:
+            O(min(n, indexDiff)) — we store at most indexDiff buckets.
+        """
+        if valueDiff < 0 or indexDiff <= 0:
+            return False
+        buckets = {}
+        bucket_size = valueDiff + 1
+        for i, num in enumerate(nums):
+            bucket_id = num // bucket_size
+            if bucket_id in buckets:
+                return True
+            if (bucket_id - 1 in buckets
+                and abs(num - buckets[bucket_id - 1]) <= valueDiff):
+                return True
+            if (bucket_id + 1 in buckets
+                and abs(num - buckets[bucket_id + 1]) <= valueDiff):
+                return True
+            buckets[bucket_id] = num
+            if i >= indexDiff:
+                del buckets[nums[i - indexDiff] // bucket_size]
+        return False

tests/test_contains_duplicate_iii_0220.py

@@ -0,0 +1,14 @@
+import pytest
+
+from solutions.contains_duplicate_iii_0220 import Solution
+
+
+@pytest.mark.parametrize(
+    'nums, index_diff, value_diff, expected', [
+        ([1,2,3,1], 3, 0, True),
+        ([1,5,9,1,5,9], 2, 3, False),
+    ]
+)
+def test_solution(nums, index_diff, value_diff, expected) -> None:
+    sol = Solution()
+    assert sol.containsNearbyAlmostDuplicate(nums, index_diff, value_diff) == expected