Caesar box / square script help urgently needed

I really need some help making a script (in php) that will encode a string with the caesars box / square method.

This method takes the string, and adds zeroes before it in order to make the string length square (my own addition) and then scrambles it as follows.

Example: hello

becomes 0000hello

write in a square as

0 0 0
0 h e
l l o

which is read off as 00l0hl0eo. any ideas?

Thanks

 

<?php
$string = 'hello';

# Zeros

while (floor(sqrt(strlen($string))) != sqrt(strlen($string))) {
 
    $string = '0'.$string;

} 

# Splitting
$str_array = explode("\r\n", chunk_split($string, sqrt(strlen($string))));

$array_size = sizeof($str_array) - 1;

$new_string = null;

# Formatting
for ($d = 0; $d < $array_size; $d++) {

	for ($i = 0; $i < $array_size; $i++) {
	
		$new_string .= $str_array[$i][$d];
		
	}
	
}

echo $new_string;
 
?>

Code (markup):

 

Thanks very much!

I had a script which worked with smaller strings, but for some reason it got buggy with larger ones. I'll implement your script, it looks perfect!

 

You could speed it up for large strings by moving those 2 sqrt(strlen($string))'s from while expression into a variable and reusing it. Good luck.