我正在使用古代涡轮增压序言。并且在以下代码中连续遇到错误：-拼写错误或未声明谓词

domains
    A,B,C = symbol
    N,P = integer

predicates
    tower(integer,symbol,symbol,symbol,integer)

    go

clauses
    go :- clearwindow,
          write(\"enter value of N (For Transfering from A To B)\"),
          readint(N),
          tower(N,\'a\',\'b\',\'c\',N).

    tower(N,A,B,C,P):-
        N > 1,
        P is N-1
        tower(P,A,C,B,P),
        write([move , A,B]),nl,
        tower(P,C,B,A,P).

        tower(0,_,_,_):- !.