(VAR L N )
(STRATEGY CONTEXTSENSITIVE
        (zeros ) 
        (cons 1) 
        (0 ) 
        (U11 1) 
        (tt ) 
        (U12 1) 
        (s 1) 
        (length 1) 
        (nil ) 
)
(RULES 
        zeros -> cons(0, zeros)
        U11(tt, L) -> U12(tt, L)
        U12(tt, L) -> s(length(L))
        length(nil) -> 0
        length(cons(N, L)) -> U11(tt, L)
        
)