Add reverse_string algorithm with type checking and examples

Author: muannn

strings/reverse_string.py

@@ -0,0 +1,44 @@
+"""
+Algorithm: Reverse String
+Author: muannn
+Description:
+    This module implements a simple function to reverse an input string.
+    It is part of the TheAlgorithms/Python open-source collection.
+
+    The algorithm takes a string `s` as input and returns the reversed version.
+    It also handles edge cases such as empty strings and single-character inputs.
+
+Example:
+    >>> reverse_string("Hello")
+    'olleH'
+
+    >>> reverse_string("OpenAI")
+    'IAnepO'
+"""
+
+def reverse_string(s: str) -> str:
+    """
+    Reverse the given string.
+
+    Args:
+        s (str): The string to be reversed.
+
+    Returns:
+        str: A new string that is the reverse of `s`.
+
+    Raises:
+        TypeError: If the input is not a string.
+    """
+    if not isinstance(s, str):
+        raise TypeError("Input must be a string.")
+
+    # Core logic: Python slicing technique to reverse string
+    return s[::-1]
+
+
+if __name__ == "__main__":
+    # Simple test cases for demonstration
+    print(reverse_string("Python"))      # Expected: 'nohtyP'
+    print(reverse_string("OpenAI"))      # Expected: 'IAnepO'
+    print(reverse_string(""))            # Expected: ''
+    print(reverse_string("A"))           # Expected: 'A'