$dogs = array('A' => 'C', 'B' => 'D', 'X' => 'Z');
$birds = array('a', 'b', 'c', 'd');
printf("%d dogs and %d birds", count($dogs), count($birds));
$birds[] = 'i';
printf("%d birds:", count($birds));
printf("%s", var_export($birds, TRUE));
$birds[10] = 'h';
unset($birds[3]);
printf("%d birds:", count($birds));
printf("%s", var_export($birds, TRUE));
?>