php中array_flip數組翻轉

<?php
$trans = array_flip($trans);
$original = strtr($str, $trans);
?>      

<?php
$trans = array("a" => 1, "b" => 1, "c" => 2);
$trans = array_flip($trans);
print_r($trans);
?>      

Array
(
    [1] => b
    [2] => c
)