PHP – Why date_diff returns unexpected result? [duplicate]

I want to get the number of days between the two dates.

// DD-MM-YYYY
$date[0] = "01-03-2023";
$date[1] = "30-03-2023";

echo date_diff(date_create($date[0]),date_create($date[1]))->d + 1;

The program above returns 2, instead of the right number of days.