Stringy thingies.

[0perator]

if i have 2 strings

 

$value_sc // scrambled value

$value_unsc //unscrambled value

 

if $value_sc = "qewryt" and $value_unsc = "qwerty"

 

how do i check both the strings to see if they contain the same characters?

[Jabop]

explode them and then asort() them, check compare array values? My best guess

[Orio]

<?php

function is_scrambled ($scrambled, $unscrambled)
{
if(strlen($scrambled) != strlen($unscrambled))
	return false;

$letters = str_split($scrambled);
$num_letters = count($letters);
sort($letters);
for($i = 0; $i < $num_letters; $i++)
	if($letters[$i] != $unscrambled[$i])
		return false;
return true;
}

?>

 

 

Orio.

[kenrbnsn]

Here's another way:

<?php
$value_sc = "qewryt";
$value_unsc = "qwerty";
$sc_arr = str_split($value_sc);
$unsc_arr = str_split($value_unsc);
sort($sc_arr);
sort($unsc_arr);
$diff = array_diff($sc_arr,$unsc_arr);
if (empty($diff)) echo 'The two strings have the same characters';
?>

 

Ken

[Barand]

After the sorts you can just compare the arrays

 

...

if ($sc_arr == $unsc_arr) echo 'The two strings have the same characters';
?>

[Orio]

After the sorts you can just compare the arrays

 

I wasn't too sure how fast str_split() is, so I thought using str_split() only once and then looping over the characters would be faster.

But I guess that should be tested.

 

Orio.

[corbin]

I would expect Orio's to be a tiny bit faster, because when you compare an array, how exactly does PHP go about doing that?  Does it check each element?  Also, you have to sort with the second one.

 

Also, Orio's would probably scale better, since operating on arrays logically becomes slower as the array gets bigger (and the rate at which a loop slows, I would assume would be slower).

 

Anyway, just a guess.

[Barand]

the main problem with Orio's is that it only works if the unscrambled string has its letters already sorted

 

echo is_scrambled('yterwq','qwerty') ? 'yes' : 'no' ;   // --> no

[corbin]

Oh you're right....  Didn't see that....  I didn't read his entire code, just looked at the main difference between the two.

 

The only way that Orio's would work would be if the unscrambled string was already sorted....

 

Guess Orio needs another str_split and sort after all x.x.

[Jabop]

kenrbnsn's method looks like it works just fine, I haven't tested it, but it's simple. I don't think the benching would really matter on such a small function

[0perator]

thanks loads

 

i used kenrbnsn method, seemed easiest for what i was doing other places in the script.

 

cheers boys