prolog code to convert decimal number to roman- programmingraja

 Aim: Write a program in prolog to convert decimal number to roman.

Software Used: SWI- PROLOG

coding:

toroman(N, _):- N < 0, !, fail.

toroman(0, []).

toroman(N, ['I'|Roman]) :- N < 4, M is N - 1, toroman(M, Roman).

toroman(4, ['IV']).

toroman(5, ['V']).

toroman(N, ['V'|Roman]) :- N < 9, M is N - 5, toroman(M, Roman).

toroman(9, ['IX']).

toroman(N, ['X'|Roman]) :- N < 40, M is N - 10, toroman(M, Roman).

toroman(N, ['XL'|Roman]) :- N < 50, M is N - 40, toroman(M, Roman).

toroman(N, ['L'|Roman]) :- N < 90, M is N - 50, toroman(M, Roman).

toroman(N, ['XC'|Roman]) :- N < 100, M is N - 90, toroman(M, Roman).

toroman(N, ['C'|Roman]) :- N < 400, M is N - 100, toroman(M, Roman).

toroman(N, ['CD'|Roman]) :- N < 500, M is N - 400, toroman(M, Roman).

toroman(N, ['DD'|Roman]) :- N < 900, M is N - 500, toroman(M, Roman).

toroman(N, ['CM'|Roman]) :- N < 1000, M is N - 900, toroman(M, Roman).

toroman(N, ['M'|Roman]) :- N < 4000, M is N - 1000, toroman(M, Roman).

roman(N, R) :- toroman(N, L), atomic_list_concat(L, R).

roman(N) :- roman(N, R), write(R).

OUTPUT :