1 sort bitvec 1 ; bit type
10 zero 1 ; bit zero
11 one 1 ; bit one
20 input 1 ; only input
100 state 1 ; first bead position
101 init 1 100 11 ; present at first
200 state 1 ; second bead position
201 init 1 200 10 ; absent at first
300 state 1 ; third bead position
301 init 1 300 10 ; absent at first
; move beads to the next position if input is 1
1100 ite 1 20 300 100
1101 next 1 100 1100
2100 ite 1 20 100 200
2101 next 1 200 2100
3100 ite 1 20 200 300
3101 next 1 300 3100