(VAR)
(RULES
c0 -> c9
c0 -> c18
c9 -> c10
c18 -> c19
c1 -> c10
c1 -> c19
c10 -> c11
c19 -> c20
c2 -> c11
c2 -> c20
c11 -> c12
c20 -> c21
c3 -> c12
c3 -> c21
c12 -> c13
c21 -> c22
c4 -> c13
c4 -> c22
c13 -> c14
c22 -> c23
c5 -> c14
c5 -> c23
c14 -> c15
c23 -> c24
c6 -> c15
c6 -> c24
c15 -> c16
c24 -> c25
c7 -> c16
c7 -> c25
c16 -> c17
c25 -> c26
c8 -> c17
c8 -> c26
c17 -> c28
c26 -> c30
c27 -> c29
c28 -> c29
c30 -> c29
)