Add problem 88 - Merge Sorted Array

Author: anirudhology

problems/array/merge_sorted_array.py

@@ -0,0 +1,29 @@
+from typing import List
+
+
+class MergeSortedArray:
+    @staticmethod
+    def merge(nums1: List[int], m: int, nums2: List[int], n: int) -> List[int]:
+        # Indices to keep track of nums1 and nums2
+        i, j = m - 1, n - 1
+        # Current index
+        index = m + n - 1
+        # Process both arrays
+        while i >= 0 and j >= 0:
+            if nums1[i] > nums2[j]:
+                nums1[index] = nums1[i]
+                i -= 1
+            else:
+                nums1[index] = nums2[j]
+                j -= 1
+            index -= 1
+        # Process remaining elements
+        while i >= 0:
+            nums1[index] = nums1[i]
+            i -= 1
+            index -= 1
+        while j >= 0:
+            nums1[index] = nums2[j]
+            j -= 1
+            index -= 1
+        return nums1

tests/array/merge_sorted_array_test.py

@@ -0,0 +1,55 @@
+import unittest
+
+from problems.array.merge_sorted_array import MergeSortedArray
+
+
+class TestMergeSortedArray(unittest.TestCase):
+
+    def setUp(self):
+        self.merge_sorted_array = MergeSortedArray()
+
+    def test_both_non_empty(self):
+        nums1 = [1, 2, 3, 0, 0, 0]
+        nums2 = [2, 5, 6]
+        m = 3
+        n = 3
+        self.assertEqual(self.merge_sorted_array.merge(nums1, m, nums2, n), [1, 2, 2, 3, 5, 6])
+
+    def test_empty_nums2(self):
+        nums1 = [1, 2, 3]
+        nums2 = []
+        m = 3
+        n = 0
+        self.assertEqual(self.merge_sorted_array.merge(nums1, m, nums2, n), [1, 2, 3])
+
+    def test_empty_nums1(self):
+        nums1 = [0, 0, 0]
+        nums2 = [1, 2, 3]
+        m = 0
+        n = 3
+        self.assertEqual(self.merge_sorted_array.merge(nums1, m, nums2, n), [1, 2, 3])
+
+    def test_empty_both(self):
+        nums1 = []
+        nums2 = []
+        m = 0
+        n = 0
+        self.assertEqual(self.merge_sorted_array.merge(nums1, m, nums2, n), [])
+
+    def test_single_element_nums1(self):
+        nums1 = [1]
+        nums2 = []
+        m = 1
+        n = 0
+        self.assertEqual(self.merge_sorted_array.merge(nums1, m, nums2, n), [1])
+
+    def test_single_element_nums2(self):
+        nums1 = [0]
+        nums2 = [1]
+        m = 0
+        n = 1
+        self.assertEqual(self.merge_sorted_array.merge(nums1, m, nums2, n), [1])
+
+
+if __name__ == '__main__':
+    unittest.main()