YES
(VAR x)
(RULES
a(b(c(b(x)))) -> c(c(b(x)))
b(c(b(a(x)))) -> b(c(c(x)))
a(a(x)) -> c(b(a(x)))
c(c(a(x))) -> c(c(c(x)))
a(b(c(c(x)))) -> c(c(x))
a(c(b(x))) -> c(b(c(b(x))))
c(c(b(c(b(x))))) -> c(b(c(b(x))))
b(c(a(c(x)))) -> b(c(c(c(x))))
a(c(a(x))) -> c(c(c(x)))
c(b(c(b(c(b(x)))))) -> c(b(c(b(x))))
c(b(c(c(x)))) -> c(c(c(x)))
a(c(c(x))) -> c(c(c(x)))
c(c(c(b(x)))) -> c(b(c(b(x))))
c(c(c(c(x)))) -> c(c(c(x)))
b(c(c(b(x)))) -> b(c(b(x)))
c(c(b(a(x)))) -> c(c(x))
c(b(a(c(x)))) -> c(a(c(x)))
b(a(b(x))) -> b(x)
)