secondChallenge.php

<?php
/**
 * Created by PhpStorm.
 * User: mockie
 * Date: 12/24/14
 */

// ================== Data =================================

$list = ['anto', 'bob', 'boby', 'susi', 'argo', 'sasi', 'szssy', 'bozki'];

// ================== Data =================================


// ================== First step is sorting the data =================================

// Sort the data using sorting method, in this case I'm using bubble sort.

// ================== First step is sorting the data =================================

function bubbleSort($list)
{
    $length = count($list)-1;

    for ($a=0; $a<$length; $a++) {
       for ($b=$a+1;$b<=$length;$b++) {
            if ($list[$a] > $list[$b]) {
                $first = $list[$a];
                $list[$a] = $list[$b];
                $list[$b] = $first;
            }
       }
    }

    return $list;
}



// ================== Second step is indexing the data =================================

// Index the first character using Btree method for fast searching next time. So we don't need to loop the entire data.

// ================== Second step is indexing the data =================================

function indexing($list)
{
    $temp = '';
    $index = [];
    $total = count($list);

    for ($a=0; $a<$total; $a++) {
        $first = substr($list[$a], 0, 1);

        if (!isset($index[$first])) {
            $index[$first]['start'] = $a;
            $temp = $first;
        }

        if ($temp != $index[$a]) {
            $index[$first]['end'] = $a;
        }
    }

    return $index;
}


$sorting = bubbleSort($list);
$index = indexing($sorting);

// ================== Third step is indexing the data =================================

// Find the name that we want to search.

// ================== Third step is indexing the data =================================

function findName($name){
    global $index;
    global $sorting;

    $firstChar = substr($name, 0, 1);
    $start = $index[$firstChar]['start'];
    $end = $index[$firstChar]['end'];

    for ($a=$start; $a<=$end; $a++)
    {
        if ($sorting[$a] == $name) {
            return $name.' found at '.$a;
            break;
        }
    }

    return 'not found';
}

echo findName('bozki').'<br />';
echo findName('sasi');

echo '<hr />';
echo 'Sorting: <br /><pre>'.print_r($sorting, true).'</pre>';
echo 'Indexing: <br /><pre>'.print_r($index, true).'</pre>';