in a scheduling program, we want to check wether two appointments overlap. For simplicity, appointments start at a full hour, and we use military time (with hours 0-24), the following pseudocode describes an algorithm that determines whether the appointment with start time /start1/ and end time /end1/ overlaps with the appointment with start time /start2/ and end time /end2/

if start1 > start2

    s = start1

else

    s = start2

if end1 < end2

    e = end1

else

    e = end2

if s < e

    the appointments overlap.

else

    the appointments don't overlap

trace this algorithm with an appointment from 10-12 and one from 11-13, then with an appointment from 10-11 and one from 12-13.