Php consolidate number (zip codes) - php

Question

I have a php array with zipcodes returned from a db query. Zip Codes are in German format so 5 digit long.
Example:
array ('90475', '90419', '90425', '90415', '90429', '90479', '90485');
I would like to consolidate the values to "ranges" with placeholder, like:
array ('90...', '904..', '9041.', '9042', '9047.');
//90485 is left out because there is only 1 match.
Edit / logic:
This is for an autosuggestion search. Trying to build a tree so users can search for entries that match any zipcode starting with 90 or 904, etc.. For the autocomplete to make sense I only want to provide the "9041." value if there is a minimum of two entries matching (90419 and 90415 in example). The zipcodes are always 5 digit long from 00000 - 99999.
Highly appreciate any help.
Thanks.

Answer 1

Here you are:
$length = 5;
$zip = array('90475', '90419', '90425', '90415', '90429', '90479', '90485');
$result = array();
for ($i = 2; $i <= $length - 1; $i++) {
$pass = array();
foreach ($zip as $val) {
$pass[substr($val, 0, $i)]++;
}
foreach ($pass as $key => $val) {
if ($val > 1) {
$result[] = $key.str_repeat('.', $length - $i);
}
}
}
sort($result);
var_dump($result);
This will return in $result an array:
array ('90...', '904..', '9041.', '9042', '9047.');
Every range, which is used only once will be ignored and not returned in $result array.

Answer 2

$myArray = array ('90475', '90419', '90425', '90415', '90429', '90479', '90485');
$consolidate = array();
foreach($myArray as $zip) {
for ($c = 2; $c < 5; ++$c) {
$key = substr($zip, 0, $c) . str_repeat('.',5 - $c);
$consolidate[$key] = (isset($consolidate[$key])) ? $consolidate[$key] + 1 : 1;
}
}
$consolidate = array_filter(
$consolidate,
function ($value) {
return $value > 1;
}
);
var_dump($consolidate);