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Reverse String Without Built-ins
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Reverse String Without Built-ins

EasyPython

Problem

Write a function that reverses a string without using built-in reverse methods or slicing shortcuts.

The function should return a new string with the characters in reverse order. Assume the input is a standard Python string and may contain letters, digits, spaces, and punctuation.

Formal Specification

  • Input: A single string s
  • Output: A string containing the characters of s in reverse order
  • Rules: Do not use built-in reverse helpers such as reversed(), ''.join(reversed(...)), or slicing with a negative step

Constraints

  • 0 <= len(s) <= 10^5
  • s may contain printable ASCII characters
  • Do not use built-in reverse helpers or negative-step slicing

Function Signature

def reverse_string(s):
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