Factors of an integer: Difference between revisions

Content added Content deleted
(→‎fac.m: Corrected a problem where the code would duplicate factors if they're perfect square roots.)
(→‎fac.m: Improved argument processing to minimize the non-relevant code and to tie the predicate/function declarations closer to the point of definition.)
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:- implementation.
:- implementation.
:- import_module float, getopt, int, list, math, string.
:- import_module float, getopt, int, list, math, string.

⚫
main(!IO) :-
⚫
io.command_line_arguments(Args, !IO),
⚫
list.foldl(print_arg, Args, !IO).


:- pred factor(int::in, list(int)::out) is det.
:- pred factor(int::in, list(int)::out) is det.
⚫
:- pred factor(int::in, int::in, int::in, list(int)::in, list(int)::out) is det.
⚫
:- func factor(int::in) = (list(int)::out) is det.

⚫
:- pred main2(list(string)::in, io::di, io::uo) is det.

factor(N, L) :-
factor(N, L) :-
Limit = float.truncate_to_int(math.sqrt(float(N))),
Limit = float.truncate_to_int(math.sqrt(float(N))),
factor(N, 2, Limit, [1,N], L).
factor(N, 2, Limit, [1,N], L).
⚫
:- pred factor(int::in, int::in, int::in, list(int)::in, list(int)::out) is det.
factor(N, X, Z, LC, L) :-
factor(N, X, Z, LC, L) :-
(X > Z ->
(X > Z ->
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).
).


⚫
:- func factor(int::in) = (list(int)::out) is det.
factor(N) = L :- factor(N, L).
factor(N) = L :- factor(N, L).


⚫
:- pred print_arg(string::in, io::di, io::uo) is det.
⚫
main(!IO) :-
⚫
print_arg(Arg, !IO) :-
⚫
io.command_line_arguments(Args, !IO),
⚫
main2(Args, !IO).

⚫
main2([], !IO) :-
io.write_string("Finished.\n", !IO).

main2([Arg|Args], !IO) :-
(string.to_int(Arg, N) ->
(string.to_int(Arg, N) ->
factor(N, X),
factor(N, X),
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;
;
io.format("Bad argument: %s\n", [s(Arg)], !IO)
io.format("Bad argument: %s\n", [s(Arg)], !IO)
),
).</lang>
main2(Args, !IO).</lang>


Use of the code looks like this:
Use of the code looks like this:
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factor(12345678, [1,2,3,6,9,18,47,94,141,282,423,846,14593,29186,43779,87558,131337,262674,685871,1371742,2057613,4115226,6172839,12345678])
factor(12345678, [1,2,3,6,9,18,47,94,141,282,423,846,14593,29186,43779,87558,131337,262674,685871,1371742,2057613,4115226,6172839,12345678])
factor(12345678) = [1,2,3,6,9,18,47,94,141,282,423,846,14593,29186,43779,87558,131337,262674,685871,1371742,2057613,4115226,6172839,12345678]
factor(12345678) = [1,2,3,6,9,18,47,94,141,282,423,846,14593,29186,43779,87558,131337,262674,685871,1371742,2057613,4115226,6172839,12345678]
Bad argument: booger
Bad argument: booger</nowiki></pre>
Finished.</nowiki></pre>


=={{header|MUMPS}}==
=={{header|MUMPS}}==
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