Problem

In the Volvo Cars app, some UI utilities need to transform text before display. Write a function that takes a string s and returns a new string with its characters in reverse order.

Formal Specification

• Input: a string s
• Output: a string containing the characters of s in reverse order
• Do not use Python's built-in reverse helpers such as slicing with [::-1] or reversed().

Examples

Example 1

Input: s = "Volvo"
Output: "ovloV"

Explanation: The characters are returned from last to first.

Example 2

Input: s = "XC40"
Output: "04CX"

Explanation: Digits and letters are reversed in the same way as any other character.

Example 3

Input: s = ""
Output: ""

Explanation: Reversing an empty string still produces an empty string.

Constraints

• 0 <= len(s) <= 10^5
• s may contain letters, digits, spaces, and punctuation
• Return a new reversed string