Gave them the Goldenballs scenario: They can either split the punishment evenly. Or try to get one of them to endure the whole punishment. But if both pick that, they both endure it for double the time.

7 10

18 10

14 31

23 32

42 0

9 10

15 31

11 0

6 10

17 10

15 31

8 30

30 34

7 0

19 34

5 0