2 files changed, 32 insertions, 0 deletions
diff --git a/prolog/problems/sets/subset_2/common.py b/prolog/problems/sets/subset_2/common.py
new file mode 100644
index 0000000..7fbbf49
--- /dev/null
+++ b/prolog/problems/sets/subset_2/common.py
@@ -0,0 +1,13 @@
+id = 133
+group = 'sets'
+number = 40
+visible = True
+facts = None
+
+solution = '''\
+subset([], []).
+subset([H|T], [H|T1]) :-
+  subset(T, T1).
+subset([_|T], T1) :-
+  subset(T, T1).
+'''
diff --git a/prolog/problems/sets/subset_2/en.py b/prolog/problems/sets/subset_2/en.py
new file mode 100644
index 0000000..9d9132b
--- /dev/null
+++ b/prolog/problems/sets/subset_2/en.py
@@ -0,0 +1,19 @@
+id = 133
+name = 'subset/2'
+slug = 'generate all subsets of a set'
+
+description = '''\
+<p><code>subset(Set, Subset)</code>: the set <code>Subset</code> is a subset of <code>Set</code>. This predicate should generate all valid solutions, one by one.</p>
+<pre>
+  ?- subset([1,2,3], SS).
+    SS = [1,2,3] ;
+    SS = [1,2] ;
+    SS = [1,3] ;
+    SS = [1] ;
+    SS = [2,3] ;
+    SS = [2] ;
+    SS = [3] ;
+    SS = [].
+</pre>'''
+
+hint = {}