2 files changed, 25 insertions, 0 deletions
diff --git a/prolog/problems/lists/shiftleft_2/common.py b/prolog/problems/lists/shiftleft_2/common.py
new file mode 100644
index 0000000..a8d56a7
--- /dev/null
+++ b/prolog/problems/lists/shiftleft_2/common.py
@@ -0,0 +1,13 @@
+id = 113
+group = 'lists'
+number = 20
+visible = True
+facts = None
+
+solution = '''\
+conc113([], L, L).
+conc113([H|T], L2, [H|L]) :-
+  conc113(T, L2, L).
+shiftleft([H|T], L2) :-
+  conc113(T, [H], L2).
+'''
diff --git a/prolog/problems/lists/shiftleft_2/en.py b/prolog/problems/lists/shiftleft_2/en.py
new file mode 100644
index 0000000..0f4b807
--- /dev/null
+++ b/prolog/problems/lists/shiftleft_2/en.py
@@ -0,0 +1,12 @@
+id = 113
+name = 'shiftleft/2'
+slug = 'shift a list left'
+
+description = '''\
+<p><code>shiftleft(L1, L2)</code>: the list <code>L2</code> is obtained from L1 by shifting elements to the left by one (circular shift).</p>
+<pre>
+  ?- shiftleft([1,2,3,4,5], X).
+    X = [2,3,4,5,1].
+</pre>'''
+
+hint = {}