Computer Science · May / June 2016 · Paper 1 HL · Question 13

13. A car park has two barriers. One barrier is at the entrance, where tickets are issued, and one barrier is at the exit, where paid tickets are checked when cars leave. A display at the entrance, showing the current availability of spaces in the car park, is updated as tickets are issued and checked. The actions of issuing, paying and checking a ticket operate on the collection of objects, TICKETS, that is organized as a linked list. Each object holds the following information: Nr: ticket number (a progressive unique identifier) Date: date of issue Arrival: time of issue (in 24-hour format) PaidOn: date of payment PaidAt: time of payment (in 24-hour format).

Read automatically from the paper; the printed page above is exact.