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School Days — 7.7

Toshi is ready to start his school days, but his schedule is all mixed up. Piece back together when he has his five classes.


1. Each class meets three times a week. Each of these meetings is on a different day.

2. The Literature class meets the same time all three days. No other class meets the same time on any two days.

3. Toshi is in class during lunch hour (noon) only on Wednesdays and Fridays.

4. Toshi always goes immediately to his Calculus classes from his Astronomy classes.

5. Toshi is a heavy sleeper, so he has 8 o’clock open Mondays–Wednesday.

6. Toshi gets mentally exhausted on Mondays, going to his Physics class immediately after his Calculus class.

7. Toshi has one day of the schedule completely clear.

8. Toshi has Geography at 8 on Thursday; his first of four classes that day. Like all times he has Geography, he has an open period immediately after.

9. Tuesday and Wednesday, Toshi has work from 10–12, and can’t be in class during those times.

10. Either Toshi has Geography at 12 Wednesday, or Literature at 12 Friday, but not both.

11. Monday is the only day Toshi has Physics but not Geography.

12. Friday has a break at 10 to rest, but that is the only time slot without a class.