Date Calculator Pro

It is a calculator that calculates the date. Being possible to do is as follows. ･Calculation of days at intervals until day at the time of which being since a certain day ･Calculation at date after ?? day from a certain day. It is a calculator that calculates the date. Being possible to do is as follows. ･Calculation of days at intervals until day at the time of which being since a certain day ･Calculation at date after ?? day from a certain day.