0 init
1 set check 1
2 add 2
3 add 0
4 constrain -2
5 constrain -1
6 constrain 0
7 constrain 1
8 constrain -2
9 constrain 2
10 constrain 0
11 add 3
12 add 2
13 add 0
14 constrain -2
15 constrain 3
16 constrain -3
17 constrain 0