wildcard array comparison - improving efficiency - php

Question

I have two arrays that I'm comparing and I'd like to know if there is a more efficient way to do it.
The first array is user submitted values, the second array is allowed values some of which may contain a wildcard in the place of numbers e.g.
// user submitted values
$values = array('fruit' => array(
'apple8756apple333',
'banana234banana',
'apple4apple333',
'kiwi435kiwi'
));
//allowed values
$match = array('allowed' => array(
'apple*apple333',
'banana234banana',
'kiwi*kiwi'
));
I need to know whether or not all of the values in the first array, match a value in the second array.
This is what I'm using:
// the number of values to validate
$valueCount = count($values['fruit']);
// the number of allowed to compare against
$matchCount = count($match['allowed']);
// the number of values passed validation
$passed = 0;
// update allowed wildcards to regular expression for preg_match
foreach($match['allowed'] as &$allowed)
{
$allowed = str_replace(array('*'), array('([0-9]+)'), $allowed);
}
// for each value match against allowed values
foreach($values['fruit'] as $fruit)
{
$i = 0;
$status = false;
while($i < $matchCount && $status == false)
{
$result = preg_match('/' . $match['allowed'][$i] . '/', $fruit);
if ($result)
{
$status = true;
$passed++;
}
$i++;
}
}
// check all passed validation
if($passed === $valueCount)
{
echo 'hurray!';
}
else
{
echo 'fail';
}
I feel like I might be missing out on a PHP function that would do a better job than a while loop within a foreach loop. Or am I wrong?
Update: Sorry I forgot to mention, numbers may occur more than 1 place within the values, but there will only ever be 1 wildcard. I've updated the arrays to represent this.

Answer 1

If you don't want to have a loop inside another, it would be better if you grouped your $match regex.
You could get the whole functionality with a lot less code, which might arguably be more efficient than your current solution:
// user submitted values
$values = array(
'fruit' => array(
'apple8756apple',
'banana234banana',
'apple4apple',
'kiwi51kiwi'
)
);
$match = array(
'allowed' => array(
'apple*apple',
'banana234banana',
'kiwi*kiwi'
)
);
$allowed = '('.implode(')|(',$match['allowed']).')';
$allowed = str_replace(array('*'), array('[0-9]+'), $allowed);
foreach($values['fruit'] as $fruit){
if(preg_match('#'.$allowed.'#',$fruit))
$matched[] = $fruit;
}
print_r($matched);
See here: http://codepad.viper-7.com/8fpThQ

Answer 2

Try replacing /\d+/ in the first array with '*', then do array_diff() between the 2 arrays
Edit: after clarification, here's a more refined approach:
<?php
$allowed = str_replace("*", "\d+", $match['allowed']);
$passed = 0;
foreach ($values['fruit'] as $fruit) {
$count = 0;
preg_replace($allowed, "", $fruit, -1, $count); //preg_replace accepts an array as 1st argument and stores the replaces done on $count;
if ($count) $passed++;
}
if ($passed == sizeof($values['fruit']) {
echo 'hurray!';
} else {
echo 'fail';
}
?>
The solution above does not remove the need for a nested loop, but it merely lets PHP do the inner loop, which may be faster (you should actually benchmark it)