Question

I have an array like so:

   array{
    [39] => src="http://www.google.com/jsapi">
    [111] => src="http://www.example.com/wp-content/themes/code.js"
    [55] => src="http://www.example.com/wp-content/themes/yui.js"
    [1015] => src="wp-content/uploads/website.jpg"
   }

Qeustion

What is the best way to find the difference of string ?

What I mean is to check if there are any duplicates.

src="http://www.example.com/wp-content/themes/ is repeated twice.

so if I then had an array like this:

array{
    [39] => src="http://www.google.com/jsapi">
    [55] => src="http://www.example.com/wp-content/themes/yui.js"
    [1015] => src="wp-content/uploads/website.jpg"
   }

http://www. is repeated twice.

so the Idea is to compare the string with another and find something that is duplicated and push it to an array … thats all that I need 🙂

I am not saying it could be possible, but it would be nice if it could be 🙂

Answer 1

Community, feel free to optimize the code. I quickly wrote this out.

function findStrDuplicate($str1, $str2)
{
    $duplicate = '';
    for($i = 0; $i < min(strlen($str1), strlen($str2)); $i++) {
        if($str1[$i] != $str2[$i]) {
            break;
        }
        $duplicate .= $str1[$i];
    }

    return $duplicate;
}

function findArrayPrefixDuplicate($array)
{
    $duplicatesArray = array();

    for($i = 0; $i < count($array) - 1; $i++) {
        for($j = $i+1; $j < count($array); $j++) {
            $dup = findStrDuplicate($array[$i], $array[$j]);
            if(!empty($dup)) {
                $duplicatesArray[] = $dup;
            }
        }
    }

    return array_unique($duplicatesArray);
}

$data = array(
    'src="http://www.google.com/jsapi"',
    'src="http://www.example.com/wp-content/themes/code.js"',
    'src="http://www.example.com/wp-content/themes/yui.js"',
    'src="wp-content/uploads/website.jpg"'
);

// Remove src="..."

$data = array_map(function ($val) {
    return substr($val, 5, strlen($val) - 1);
}, $data);

$result = findArrayPrefixDuplicate($data);

var_dump($result);

Result:

array
  0 => string 'http://www.' (length=11)
  2 => string 'http://www.example.com/wp-content/themes/' (length=41)