Model your daily schedule with a timed automaton. Hours are reflected by a variable h, days by a variable d. d = 1 means Monday, d = 7 means Sunday. On a weekend (d = 6 or d = 7), you leave the sleeping state between h = 10 and h = 11, spend 1–2 h getting yourself ready for the day, stay with your friend until some time in the range h = 20 to h = 21, and walk back home and enter the sleeping state between h = 22 and h = 23. During the week (d = 1 or …or d = 5), you leave the sleeping state between h = 7 and h = 8, spend 1–2 h getting yourself ready for the day, study until some time in the range h = 20 to h = 21, and walk back home and enter the sleeping state between h = 22 and h = 23. Model your schedule! Do not forget to increase the day d at the end of each day.