用php輸出一個數組中的偶數或奇數的方法

function odd($var){ // returns whether the input integer is odd 
 return($var & 1);
}

function even($var){ // returns whether the input integer is even 
 return(!($var & 1));
}

$array1 = array("a"=>1, "b"=>2, "c"=>3, "d"=>4, "e"=>5);
$array2 = array(6, 7, 8, 9, 10, 11, 12);

echo "Odd :
";
print_r(array_filter($array1, "odd"));
echo "Even:
";print_r(array_filter($array2, "even"));