YES

---- CR(R)
---- Hot decreasingness.
R:
f(a(),a(),b(),b()) -> f(c(),c(),c(),c())
a() -> b()
a() -> c()
b() -> a()
b() -> c()

C:


Label:
[f(a(),a(),b(),b()) -> f(c(),c(),c(),c())] = 0
[a() -> b()] = 2
[a() -> c()] = 0
[b() -> a()] = 1
[b() -> c()] = 0