Reverse a String Without Built-in Functions

Given a string, your task is to reverse it without using any built-in reverse functions. You should implement the reversal logic manually by iterating over the string. This problem tests your understanding of string manipulation and basic loop constructs.

For example, given the input string "hello", the output should be "olleh". Similarly, a palindrome like "madam" will remain unchanged after reversal.

Note: You must read input from stdin and write output to stdout for the submitted solution.

You can refer to the following transformation formula in LaTeX for the reverse operation:

$$\text{reverse}(s) = s[n-1] \; s[n-2] \; \dots \; s[0]$$

inputFormat

The input consists of a single line containing a non-empty string s, whose length does not exceed 10⁵ characters.

Input is provided through stdin.

outputFormat

Output a single line which is the reverse of the provided string.

Output must be written to stdout.

## sample

hello

olleh