Merge pull request #13014 from 2colours/branch-for-challenge-346

Branch for challenge 346

2 files changed, 45 insertions, 0 deletions

diff --git a/challenge-346/2colours/prolog/ch-1.p b/challenge-346/2colours/prolog/ch-1.p
new file mode 100644
index 0000000000..5f965bed84
--- /dev/null
+++ b/challenge-346/2colours/prolog/ch-1.p
@@ -0,0 +1,27 @@
+:- use_module(library(dcg/basics)).
+
+paren_compositions_min1 --> paren_composition, paren_compositions.
+
+paren_compositions --> paren_compositions_min1.
+paren_compositions --> [].
+
+paren_composition --> `(`, paren_compositions, `)`.
+
+candidate_length(Str, L) :-
+        string_length(Str, Str_Len),
+        candidate_length(Str, Str_Len, L).
+
+candidate_length(Str, Str_L, C_L) :-
+        string_codes(Str, Str_Codes),
+        phrase((string(Prefix), paren_compositions_min1), Str_Codes, Postfix),
+        length(Postfix, Rem_L),
+        (
+                length(Prefix, Skipped_L),
+                C_L is Str_L - Rem_L - Skipped_L
+        ;
+                candidate_length(Postfix, Rem_L, C_L)
+        ).
+        
+
+
+task(Str, Result) :- findall(L, candidate_length(Str, L), Ls), max_list(Ls, Result).
diff --git a/challenge-346/2colours/prolog/ch-2.p b/challenge-346/2colours/prolog/ch-2.p
new file mode 100644
index 0000000000..7afa2f7d2f
--- /dev/null
+++ b/challenge-346/2colours/prolog/ch-2.p
@@ -0,0 +1,18 @@
+:- use_module(library(dcg/basics)).
+:- use_module(library(dcg/high_order)).
+
+
+operator --> `*`.
+operator --> `+`.
+operator --> `-`.
+operator --> ``.
+
+good_expression(Str, Target, Expression) :-
+	string_codes(Str, Str_Codes),
+	phrase(sequence(digit, operator, Str_Codes), Expression_Codes),
+	string_codes(Expression, Expression_Codes),
+	read_term_from_atom(Expression, Term, []),
+	Term =:= Target.
+
+
+task(Str, Target, Expressions) :- findall(Expression, good_expression(Str, Target, Expression), Expressions).