lane actor#1 "black" @7:15
lane actor#2 "white" @8:15
region seq#1 seq
region loop#1 loop parent=seq#1 @11:1
step ask#1~actor#1 ask "ask" @12:40 lane=actor#1 lanes=actor#1,actor#2 source=ask#1 region=loop#1 maybe serial
step ask#1~actor#2 ask "ask" @12:40 lane=actor#2 lanes=actor#1,actor#2 source=ask#1 region=loop#1 maybe serial
edge ask#1~actor#1 -> ask#1~actor#1 carry maybe
edge ask#1~actor#1 -> ask#1~actor#2 carry maybe
edge ask#1~actor#2 -> ask#1~actor#1 carry maybe
edge ask#1~actor#2 -> ask#1~actor#2 carry maybe
sink ask#1~actor#1,ask#1~actor#2
