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prolog convert numbers into roman numerals

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问题 i have this code that converts integers into roman numerals i need to add a function that compares an integer with a roman numeral input and show if it's try or false, for example: roman(v,5). true toroman(0). toroman(N) :- N < 4, put("I"), M is N - 1, toroman(M). toroman(N) :- N = 4, put("I"), put("V"). toroman(N) :- N = 5, put("V"). toroman(N) :- N < 9, put("V"), M is N - 5, toroman(M). toroman(N) :- N = 9, put("I"), put("X"). toroman(N) :- N < 40, put("X"), M is N - 10, toroman(M). toroman

Prolog - Parsing

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问题 I'm new to the language prolog and have been given an assignment regarding parsing in prolog. I need some help in solving the problem. In the assingment we have the grammar: Expr ::= + Expr Expr | * Expr Expr | Num | Xer Xer ::= x | ^ x Num Num ::= 2 | 3 | .... a Integer (bigger than 1) ... The token ^ is the same as in math. 5^5 equals 25 . Parse needs to work both ways: a call with an instantiated list to generate an Ast, while a call with an instantiated Ast should generate similar prefix

How is this context free grammar using difference lists in Prolog functioning?

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问题 I'm reading this tutorial on context free grammars in Prolog, and they mention at the bottom of the page implementing a context free grammar in Prolog using difference lists, with the following code block included: s(X,Z):- np(X,Y), vp(Y,Z). np(X,Z):- det(X,Y), n(Y,Z). vp(X,Z):- v(X,Y), np(Y,Z). vp(X,Z):- v(X,Z). det([the|W],W). det([a|W],W). n([woman|W],W). n([man|W],W). v([shoots|W],W). It mentions: Consider these rules carefully. For example, the s rule says: I know that the pair of lists

RegEx Parser written in Prolog

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问题 I've been banging my head against the wall on this homework problem for a few hours now. We have to parse a regular expression with Prolog. For the most part, the predicates I have work, but there's a few regular expression and string combos which cause them to run out of stack space in SWI-Prolog. Here's a sample with two of the Regex string combinations, one that works and one that doesn't: star(star(char(a))), [] star(star(char(a))), [a] The first one works and the second one runs out of

Prolog List Plateau

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Just got introduced to prolog, trying to get through some simple exercises, but I've been getting kind of stuck on this one. I'm trying to write a program that outputs all the sublists of the input list, where each sublist has length > 1 and it cannot be extended to a larger sublist. It will also output the starting position in the list of the sublist. So a sample output would be | ?- plateau([a,a,b,2,2,2,a+1,a+1,s(1,2)], I, Len). I = 1, Len = 2 ? ; I = 4, Len = 3 ? ; I = 7, Len = 2 ? ; no I'm still pretty confused by the whole declarative thing, and having a lot of trouble switching out of

prolog convert numbers into roman numerals

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i have this code that converts integers into roman numerals i need to add a function that compares an integer with a roman numeral input and show if it's try or false, for example: roman(v,5). true toroman(0). toroman(N) :- N < 4, put("I"), M is N - 1, toroman(M). toroman(N) :- N = 4, put("I"), put("V"). toroman(N) :- N = 5, put("V"). toroman(N) :- N < 9, put("V"), M is N - 5, toroman(M). toroman(N) :- N = 9, put("I"), put("X"). toroman(N) :- N < 40, put("X"), M is N - 10, toroman(M). toroman(N) :- N < 50, put("X"), put("L"), M is N - 40, toroman(M). toroman(N) :- N < 90, put("L"), M is N - 50

Sentence parsing and matching in Prolog

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I'm trying to create a sentence parser in Prolog. I want the sentence to be parsed into three separate lists that will be matched with a suggested outcome. For example, here's the code I have come up with so far... This is the vocabulary which will be used to parse certain words: det(the). det(a). det(an). noun(cat). noun(boy). noun(girl). noun(grandfather). noun(person). noun(mat). noun(party). noun(book). noun(problem). noun(father). noun(student). noun(golf). noun(conversation). noun(challenge). noun(person). noun(problem). noun(sat). verb(thrives). verb(loves). verb(likes). prep(on). prep

Prolog List Plateau

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问题 Just got introduced to prolog, trying to get through some simple exercises, but I've been getting kind of stuck on this one. I'm trying to write a program that outputs all the sublists of the input list, where each sublist has length > 1 and it cannot be extended to a larger sublist. It will also output the starting position in the list of the sublist. So a sample output would be | ?- plateau([a,a,b,2,2,2,a+1,a+1,s(1,2)], I, Len). I = 1, Len = 2 ? ; I = 4, Len = 3 ? ; I = 7, Len = 2 ? ; no I

Sentence parsing and matching in Prolog

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问题 I'm trying to create a sentence parser in Prolog. I want the sentence to be parsed into three separate lists that will be matched with a suggested outcome. For example, here's the code I have come up with so far... This is the vocabulary which will be used to parse certain words: det(the). det(a). det(an). noun(cat). noun(boy). noun(girl). noun(grandfather). noun(person). noun(mat). noun(party). noun(book). noun(problem). noun(father). noun(student). noun(golf). noun(conversation). noun

Remove Ambiguity in abstract syntax in other to write DCG parser Prolog

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