Compare keys and values of two arrays with two user functions for comparison and return differences in PHP

//from   w  ww.j  av a2 s.c o  m
<?php
function myfunction_key($a,$b){
   if ($a===$b){
      return 0;
    }
    return ($a>$b)?1:-1;
}

function myfunction_value($a,$b){
   if ($a===$b){
     return 0;
   }
   return ($a>$b)?1:-1;
}

$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("a"=>"red","b"=>"Green","c"=>"green");

$result=array_udiff_uassoc($a1,$a2,"myfunction_key","myfunction_value");
print_r($result);
?>