Form a new string with data from an array PHP - php

Question

I would need to reduce the quantity of these numbers and present them in a more concise way, instead of presenting several lines of numbers with the same "prefix" or "root". For example:
If I have an array like this, with several strings of numbers (obs: only numbers and the array is already sorted):
$array = array(
"12345647",
"12345648",
"12345649",
"12345657",
"12345658",
"12345659",
);
The string: 123456 is the same in all elements of the array, so it would be the root or the prefix of the number. According to the above array I would get a result like this:
//The numbers in brackets represent the sequence of the following numbers,
//instead of showing the rows, I present all the above numbers in just one row:
$stringFormed = "123456[4-5][7-9]";
Another example:
$array2 = array(
"1234",
"1235",
"1236",
"1247",
"2310",
"2311",
);
From the second array, I should get a result like this:
$stringFormed1 = "123[4-7]";
$stringFormed2 = "1247";
$stringFormed3 = "231[0-1]";
Any idea?

Answer 1

$array = array(
"12345647",
"12345648",
"12345649",
"12345657",
"12345658",
"12345659",
);
//find common string positions for all elements
$res = array();
foreach($array as $arr){
for($i=0;$i<strlen($arr);$i++){
$res[$i][$arr[$i]] = $arr[$i];
}
}
//make final string
foreach($res as $pos){
if(count($pos)==1)
$str .= implode('',$pos);
else{
//u may need to sort these values if you want them in order
$end = end($pos);
$first = reset($pos);
$str .="[$first-$end]";
}
}
echo $str; // "123456[4-5][7-9]";

Answer 2

Well, as I understand you want the final string with unique characters. (i'm not sure if you want it ordered)
So, first implode to create the string
$stringFormed = implode("", $array);
Then we get the unique chars :
$stringFormed=implode("",array_unique(str_split($stringFormed)));
OUTPUT: 123456789

Answer 3

That as a solution for first example but i didn't thought there could be several roots.
By the way i'm not sure it's well coded...
<?php
function longest_common_substring($words)
{
$words = array_map('strtolower', array_map('trim', $words));
$sort_by_strlen = create_function('$a, $b', 'if (strlen($a) == strlen($b)) { return strcmp($a, $b); } return (strlen($a) < strlen($b)) ? -1 : 1;');
usort($words, $sort_by_strlen);
// We have to assume that each string has something in common with the first
// string (post sort), we just need to figure out what the longest common
// string is. If any string DOES NOT have something in common with the first
// string, return false.
$longest_common_substring = array();
$shortest_string = str_split(array_shift($words));
while (sizeof($shortest_string)) {
array_unshift($longest_common_substring, '');
foreach ($shortest_string as $ci => $char) {
foreach ($words as $wi => $word) {
if (!strstr($word, $longest_common_substring[0] . $char)) {
// No match
break 2;
} // if
} // foreach
// we found the current char in each word, so add it to the first longest_common_substring element,
// then start checking again using the next char as well
$longest_common_substring[0].= $char;
} // foreach
// We've finished looping through the entire shortest_string.
// Remove the first char and start all over. Do this until there are no more
// chars to search on.
array_shift($shortest_string);
}
// If we made it here then we've run through everything
usort($longest_common_substring, $sort_by_strlen);
return array_pop($longest_common_substring);
}
$array = array(
"12345647",
"12345648",
"12345649",
"12345657",
"12345658",
"12345659",
);
$result= longest_common_substring($array);
for ($i = strlen($result); $i < strlen($array[0]); $i++) {
$min=intval($array[0][$i]);
$max=$min;
foreach ($array as $string) {
$val = intval($string[$i]);
if($val<$min)
$min=$val;
elseif($val>$max)
$max=$val;
}
$result.='['.$min.'-'.$max.']';
}
echo $result;
?>