3.Reverse An Array with test case

Author: PTHARRISH

geek_for_geeks/challenge/Secondlargest.py

@@ -1,3 +1,4 @@
+# 1.Second Largest 
 # Using One Iteration(Best method)
 def getSecondLargest(arr):
     n = len(arr)

geek_for_geeks/challenge/reverse_an_array.py

@@ -0,0 +1,26 @@
+# 3.Reverse An Array
+# Two Pointer Approach (best approach)
+def reverseArray(arr):
+    n = len(arr)
+    for i in range(n // 2):
+        arr[i], arr[n - 1 - i] = arr[n - 1 - i], arr[i]
+    return arr
+
+
+# T.C = O(n)
+# S.C = O(1)
+
+
+# Naive method
+def reverseArray(arr):
+    temp = []
+    n = len(arr)
+    for i in range(n):
+        temp.append(arr[n - 1 - i])
+    # for i in range(len(arr) - 1, -1, -1):
+    #     temp.append(arr[i])
+    return temp
+
+
+# T.C = O(n)
+# S.C = O(n)

test/test_case.py

@@ -3,6 +3,7 @@
 
 sys.path.append(os.path.abspath(".."))
 from geek_for_geeks.challenge.move_zero import pushZerosToEnd
+from geek_for_geeks.challenge.reverse_an_array import reverseArray
 from geek_for_geeks.challenge.secondlargest import getSecondLargest
 
 
@@ -65,3 +66,33 @@ def test_mixed_types(self):
         expected = [1, 2, 3, 0, 0, 0, 0]
         pushZerosToEnd(arr)
         assert arr == expected
+
+
+class TestReverseArray:
+    def test_even_length(self):
+        arr = [1, 2, 3, 4]
+        expected = [4, 3, 2, 1]
+        assert reverseArray(arr) == expected
+
+    def test_odd_length(self):
+        arr = [1, 2, 3, 4, 5]
+        expected = [5, 4, 3, 2, 1]
+        assert reverseArray(arr) == expected
+
+    def test_single_element(self):
+        arr = [7]
+        expected = [7]
+        assert reverseArray(arr) == expected
+
+    def test_empty_list(self):
+        arr = []
+        expected = []
+        assert reverseArray(arr) == expected
+
+    def test_palindrome_list(self):
+        arr = [1, 2, 3, 2, 1]
+        expected = [1, 2, 3, 2, 1]
+        assert reverseArray(arr) == expected
+
+
+U