SWI Prolog中的Hangman游戏
我正在尝试在SWI Prolog中制作一个简单的子手游戏。
既然我们使该程序运行了，那么您可以通过以下方法帮助我增强该程序：
跟上到目前为止已经猜到的字母。如果用户猜到了已经猜到的字母，程序应说“您猜到了！”。然后继续游戏。
最后，添加一个计数器，用于计算错误猜想的数量，并在达到一定数量时退出游戏。该程序应告知用户他们输了，显示该短语的真正含义并终止。重复的猜测不应被认为是错误的。
我为您提供代码和注释。
% This top-level predicate runs the game. It prints a % welcome message, picks a phrase, and calls getGuess.
% Ans = Answer
% AnsList = AnswerList
hangman:-
getPhrase(Ans),
!,
write('Welcome to hangman.'),
nl,
name(Ans,AnsList),
makeBlanks(AnsList, BlankList),
getGuess(AnsList,BlankList).
% Randomly returns a phrase from the list of possibilities.
getPhrase(Ans):-
phrases(L),
length(L, X),
R is random(X),
N is R+1,
getNth(L, N, Ans).
% Possible phrases to guess.
phrases(['a_picture_is_worth_a_thousand_words','one_for_the_money','dead_or_alive','computer_science']).
% Asks the user for a letter guess. Starts by writing the
% current "display phrase" with blanks, then asks for a guess and
% calls process on the guess.
getGuess(AnsList, BlankList):-
name(BlankName, BlankList),
write(BlankName),
nl,
write('Enter your guess, followed by a period and return.'),
nl,
read(Guess),
!,
name(Guess, [GuessName]),
processGuess(AnsList,BlankList,GuessName).
% Process guess takes a list of codes representing the answer, a list of codes representing the current
% "display phrase" with blanks in it, and the code of the letter that was just guessed. If the guess
% was right, call substitute to put the letter in the display phrase and check for a win. Otherwise, just
% get another guess from the user.
processGuess(AnsList,BlankList,GuessName):-
member(GuessName,AnsList),
!,
write('Correct!'),
nl,
substitute(AnsList, BlankList, GuessName, NewBlanks),
checkWin(AnsList,NewBlanks).
processGuess(AnsList, BlankList,_):-
write('Nope!'),
nl,
getGuess(AnsList, BlankList).
% Check to see if the phrase is guessed. If so, write 'You win' and if not, go back and get another guess.
checkWin(AnsList, BlankList):-
name(Ans, AnsList),
name(BlankName, BlankList),
BlankName = Ans,
!,
write('You win!').
checkWin(AnsList, BlankList):-
!,
getGuess(AnsList, BlankList).
% getNth(L,N,E) should be true when E is the Nth element of the list L. N will always
% be at least 1.
getNth([H|T],1,H).
getNth([H|T],N,E):-
N1 is N-1,
getNth(T,N1,E1),
E=E1.
% makeBlanks(AnsList, BlankList) should take an answer phrase, which is a list
% of character codes that represent the answer phrase, and return a list
% where all codes but the '_' turn into the code for '*'. The underscores
% need to remain to show where the words start and end. Please note that
% both input and output lists for this predicate are lists of character codes.
% You can test your code with a query like this:
% testMakeBlanks:- name('csc_is_awesome', List), makeBlanks(List, BlankList), name(Towrite, BlankList), write(Towrite).
makeBlanks(AnsCodes, BlankCodes) :-
maplist(answer_blank, AnsCodes, BlankCodes).
answer_blank(Ans, Blank) :-
Ans == 0'_ -> Blank = Ans ; Blank = 0'* .
% substitute(AnsList, BlankList, GuessName, NewBlanks) Takes character code lists AnsList and BlankList,
% and GuessName, which is the character code for the guessed letter. The NewBlanks should again be a
% character code list, which puts all the guesses into the display word and keeps the *'s and _'s otherwise.
% For example, if the answer is 'csc_is_awesome' and the display is 'c*c_**_*******' and the guess is 's', the
% new display should be 'csc_*s_***s***'.
% You can test your predicate with a query like this:
% testSubstitute:- name('csc_is_awesome', AnsList), name('c*c_**_*******', BlankList), name('s',[GuessName]), substitute(AnsList, BlankList, GuessName, NewBlanks),
% name(Towrite, NewBlanks), write(Towrite).
% Also, since the predicate doesn't deal directly with character codes, this should also work:
% substitute(['c','s','c'],['c','*','c'],'s',L). L should be ['c','s','c'].
substitute(AnsCodes, BlankCodes, GuessName, NewBlanks) :-
maplist(place_guess(GuessName), AnsCodes, BlankCodes, NewBlanks).
place_guess(Guess, Ans, Blank, Display) :-
Guess == Ans -> Display = Ans ; Display = Blank.
回答：
maplist
/ 3＆maplist / 4将其第一个参数（适当Arity的谓词）应用于其他参数列表的所有元素，那么您的makeBlanks可能是：
makeBlanks(AnsCodes, BlankCodes) :- maplist(answer_blank, AnsCodes, BlankCodes).
answer_blank(Ans, Blank) :-
Ans == 0'_ -> Blank = Ans ; Blank = 0'* .
并替换为：
substitute(AnsCodes, BlankCodes, GuessName, NewBlanks) :- maplist(place_guess(GuessName), AnsCodes, BlankCodes, NewBlanks).
place_guess(Guess, Ans, Blank, Display) :-
Guess == Ans -> Display = Ans ; Display = Blank.
：
根据其他要求：1）可以使用其他谓词解决：
alreadyGuessed(Guess, AnsCodes) :- memberchk(Guess, AnsCodes).
而问候2）getGuess并processGuess一起构成一个循环，当没有更多呼叫发生时，循环将终止。删除checkWin的最后一条规则，添加一个参数作为计数器来跟踪失败的猜测，并扩展processGuess来指示失败：
processGuess(AnsList, BlankList, _, CountFailed) :- ( CountFailed == 5
-> format('Sorry, game over. You didn\'t guess (~s)~n', [AnsList])
; write('Nope!'),
CountFailed1 is CountFailed + 1,
getGuess(AnsList, BlankList, CountFailed1)
).
以上是 SWI Prolog中的Hangman游戏 的全部内容， 来源链接： utcz.com/qa/400103.html
