如何使用PHP对数组进行排序[关闭]

Say that i have an array like this :

$arr_sequences = 
    array('00-02', '02-03', '03-07', '23-03', '03-23', '07-11', '11-10', '11-11');

How to sort the array so the values would look like this :

$arr_sequences = 
    array('00-02', '02-03', '03-23', '23-03', '03-07', '07-11', '11-11', '11-10');

If we look closely each value has an id (code) that's divided by -
For example :

$arr_sequences[2] = '03-07'; // '07' as last code, then search another value with '07' in front of the value

Then next index value shoud be

$arr_sequences[5] = '07-11'; // '07' front, then search '11' as next value

the goal is to sort the array without losing any length.

I have tried with tree algorithm, but I can't get it to work.

The crazy approach:

1. Generate all possible permutations
2. Loop through each permutation and see if there is a domino effect and add it to the output

The PHP code

$arr_sequences = array('00-02', '02-03', '03-07', '23-03', '03-23', '07-11', '11-10', '11-11'); // Input

$permutations = permutations($arr_sequences); // Generating permutations

// Generating a regex
$n = count($arr_sequences);
$regex = '\d+';
for($i=1;$i<$n;$i++){
    $regex .= '-(\d+)-\\'.$i;
}
$regex .= '-\d+';

$sorted = preg_grep('#'.$regex.'#', $permutations); // Filtering the permutations
sort($sorted); // re-index the keys

//generating the desired output
$output = array();
foreach($sorted as $key => $sample){
    $temp = explode('-', $sample);
    $c = count($temp); // Micro-optimization, yeaaaah!
    for($i=0;$i<$c;$i+=2){
        $output[$key][] = $temp[$i] . '-' . $temp[$i+1];
    }
}

print_r($output); // printing

// Function from http://stackoverflow.com/a/14998162
function permutations($elements) {
    if(count($elements)<2) return $elements;
    $newperms= array();
    foreach($elements as $key=>$element) {
        $newelements= $elements;
        unset($newelements[$key]);

        $perms= permutations($newelements);
        foreach($perms as $perm) {
            $newperms[]= $element."-".$perm;
        }
    }
    return $newperms;
}

The output

Array
(
    [0] => Array
        (
            [0] => 00-02
            [1] => 02-03
            [2] => 03-23
            [3] => 23-03
            [4] => 03-07
            [5] => 07-11
            [6] => 11-11
            [7] => 11-10
        )

)

_{It seems that there was only one solution :p}

A Brute Force way, in php. (Not tested):

<?php

$arr = array('00-02', '02-03', '03-07', '23-03', '03-23', '07-11', '11-10', '11-11');

function findMatches($i, $val_ignore, $arr) {
    $arr_matches = array();
    foreach($arr as $key => $val) {
      $j = substr_replace($val, '', 2);
      if (($i == $j) && ($val != $val_ignore))
        $arr_matches[] = $val;
    }
    return $arr_matches;
}

$arr_sorted = array();
foreach($arr as $key => $val) {
    $i = substr_replace($val, '', 0, 3);
    if (!in_array($val, $arr_sorted)) $arr_sorted[] = $val;
    $arr_sorted = array_merge($arr_sorted, findMatches($i, $val, $arr));
}

?>