PHP 数组函数 array_udiff_assoc()

<?php
   function call_back_function($v1,$v2) {
      if ($v1 === $v2) {
         return 0;
      }
      return 1;
   }
   $input = array("a"=>"orange","b"=>"orange","c"=>"mango");
   $input1 = array("a"=>"orange","b"=>"mango","c"=>"orange");

   print_r(array_udiff_assoc($input,$input1,"call_back_function"));
?>