word combo

<?php

$str = \"apple pear banana orange\";
$str_splode = explode(\' \',$str);
$combos = showCombo(array(), $str_splode);
foreach($combos as $key=>$array){
    echo $key.PHP_EOL;
    displayArrayByKey($key, $array);
}


function displayArrayByKey($str, $arr){
    foreach($arr as $key=>$array){
          $string = $str. \" \" . $key;
          echo $string . PHP_EOL; 
          if(count($array)> 0){
              displayArrayByKey($string, $array);
          }
    }
}

function showCombo($str_arr, $arr){
    $ret = array();
    foreach($arr as $val){
       if(!in_array($val, $str_arr)){
           $temp = $str_arr;
           $temp[] = $val;
           $ret[$val] = showCombo($temp, $arr);
       }
    }
    return $ret;
}

?>