EQUATIONS: 
fib(0()) = s(0())
fib(s(0())) = s(0())
fib(s(s(x))) = plus(fib(s(x)),fib(x))
dfib(0()) = s(0())
dfib(s(0())) = s(0())
dfib(s(s(x))) = plus(dfib(s(x)),plus(dfib(x),dfib(x)))
plus(x,s(y)) = s(plus(x,y))
plus(x,0()) = x
minus(s(x),s(y)) = minus(x,y)
minus(x,0()) = x
p(x) = minus(x,s(0()))

COMPLETE TRS:
RULES:
fib(0()) -> s(0())
fib(s(0())) -> s(0())
fib(s(s(x))) -> plus(fib(s(x)),fib(x))
dfib(0()) -> s(0())
dfib(s(0())) -> s(0())
dfib(s(s(x))) -> plus(dfib(s(x)),plus(dfib(x),dfib(x)))
plus(x,s(y)) -> s(plus(x,y))
plus(x,0()) -> x
minus(s(x),s(y)) -> minus(x,y)
minus(x,0()) -> x
minus(x,s(0())) -> p(x)
p(s(x)) -> x

SUCCESS
MaxTRS: 6 
Search time: 46.15 seconds