Need to find census by date and hour of day based off of arrival and discharge date/time

I have a file that contains date and time of arrival and discharge of patients. I need a way of counting the total number of patients that were present for each hour of each day of the month without hand plotting.

My data is formatted as such for each patient:

Arrived Disch Date/Time
09/09/15 1306 09/11/2015 1617


How do I format my sheet and create calculations to count a 1 for this patient for 1pm-12pm on the 9th, all 24 hours of the 10th and then 12am-5pm on the 11th?

Please help, I'm desperate!