Replacing char with number - php

Question

There is this code that I am doing
Example a string of this value
z12z
I want to generate it
0120
0121
0122
... until 0129
then
1120
1121
1122
... until 1129
until 9129 , its sort of like two four loop, but I got no idea how to implement this.
and the issue is z can be anywhere and it can be zzzz
where it will be
0000 until 9999
or it could also be z0z0, z could be anywhere. What kind of method should I use for such.
Thanks!
I am doing it with php
for every occurance of letter 'z' , i will need do a for loop to generate the possible number, from 0 to 9, you can say z is a for loop for 0 to 9, e.g z555 will yield 0555,1555,2555,3555,4555,5555,6555,7555,8555,9555 , issue is z can occur with a possibility of 0 to 4, like z555 , zz55,zzz5, zzzz, and z position is random , I need generate the possible z number output
z position could be 55z5 , 5z55 , 5zz5 . its does not have a fix position.

Answer 1

<?php
$numbers = array();
for ($i = 0; $i <= 9; $i++){
for ($j = 120; $j <= 129; $j++){
$numbers[] = $i . $j;
}
}
print_r('<pre>');
print_r($numbers);
A better answer that take the z char is:
<?php
function strReplaceNth($search, $replace, $subject, $nth)
{
$found = preg_match_all('/' . preg_quote($search) . '/', $subject, $matches, PREG_OFFSET_CAPTURE);
if (false !== $found && $found > $nth) {
return substr_replace($subject, $replace, $matches[0][$nth][1], strlen($search));
}
return $subject;
}
function cleanup($numbers, $char)
{
$tmp = array();
for ($i = 0; $i < count($numbers); $i++){
if (strpos($numbers[$i], $char) === false){
$tmp[] = $numbers[$i];
}
}
return $tmp;
}
function generateNumber($numbers, $char)
{
if (!is_array($numbers)){
if (strpos($numbers, $char) === false){
return array($numbers);
} else {
$tmp = $numbers;
$numbers = array();
for ($j = 0; $j <= 9; $j++){
$numbers[] = strReplaceNth($char, $j, $tmp, 0);
}
return generateNumber($numbers, $char);
}
} else {
for ($i = 0; $i < count($numbers); $i++){
if (strpos($numbers[$i], $char) === false){
return cleanup($numbers, $char);
} else {
$numbers = array_merge($numbers, generateNumber($numbers[$i], $char));
}
}
return generateNumber($numbers, $char);
}
}
function getCharPos($string, $char)
{
$pos = array();
for ($i = 0; $i < strlen($string); $i++){
if (substr($string, $i, 1) == $char){
$pos[] = $i;
}
}
return $pos;
}
$string = 'z12z';
$char = 'z';
$occurences = getCharPos($string, $char);
$numbers = array();
if (count($occurences) > 0){
$numbers = generateNumber($string, $char);
} else {
$numbers[] = $string;
}
print_r('<pre>');
print_r($numbers);die();