Reverse a string in JS & PHP using this `str_reverse()` function

str_reverse.js

const readline = require("node:readline");

const input = readline.createInterface({
	input: process.stdin,
	output: process.stdout
});

const str_reverse = (string) => {
	let reverse = "";
	for (let index = string.length; index > 0; index--)
		reverse += string[index - 1];
	return reverse;
};

input.question(`\nEnter any string: `, (string) => {
	console.log(
		`\n=========\nInput: '${string}'\nOutput: '${str_reverse(string)}'\n`
	);
	input.close();
});

str_reverse.php

<?php

$input = readline("Enter a string: ");
echo "\n";

function str_reverse($string)
{
    $output = "";
    $cnt = 0;
    for($i = strlen($string); $i > 0; $i--)
        $output[$cnt++] = $string[$i - 1];

    return $output;
}

echo "input: '$input'\n";
echo "output: '" . str_reverse($input) . "'\n";

// TEST: $ php str_reverse.php 
// Enter a string: alialmasi
// 
// input: 'alialmasi'
// output: 'isamlaila'