Prolog: add problem lists/last_elem_2

3 files changed, 80 insertions, 0 deletions

diff --git a/prolog/problems/lists/last_elem_2/common.py b/prolog/problems/lists/last_elem_2/common.py
new file mode 100644
index 0000000..b18243d
--- /dev/null
+++ b/prolog/problems/lists/last_elem_2/common.py
@@ -0,0 +1,46 @@
+from operator import itemgetter
+import prolog.engine
+import prolog.util
+import socket
+from server.hints import Hint, HintPopup
+import server.problems
+
+id = 10000
+number = 2
+visible = True
+facts = None
+
+solution = '''\
+'''
+
+hint_type = {
+}
+
+test_cases = [
+    ('last_elem([X], c)',
+        [{'X': 'c'}]),
+    ('last_elem([y, l, r, g, a], X)',
+        [{'X': 'a'}]),
+]
+
+def test(code, aux_code):
+    n_correct = 0
+    engine_id = None
+    try:
+        engine_id, output = prolog.engine.create(code=code+aux_code, timeout=1.0)
+        if engine_id is not None and 'error' not in map(itemgetter(0), output):
+            # Engine successfully created, and no syntax error in program.
+            for query, answers in test_cases:
+                if prolog.engine.check_answers(engine_id, query=query, answers=answers, timeout=1.0):
+                    n_correct += 1
+    except socket.timeout:
+        pass
+    finally:
+        if engine_id:
+            prolog.engine.destroy(engine_id)
+
+    hints = [{'id': 'test_results', 'args': {'passed': n_correct, 'total': len(test_cases)}}]
+    return n_correct, len(test_cases), hints
+
+def hint(code, aux_code):
+    return []
diff --git a/prolog/problems/lists/last_elem_2/en.py b/prolog/problems/lists/last_elem_2/en.py
new file mode 100644
index 0000000..93c7c05
--- /dev/null
+++ b/prolog/problems/lists/last_elem_2/en.py
@@ -0,0 +1,13 @@
+name = 'last_elem/2'
+slug = 'find last element in list'
+
+description = '''\
+<p><code>last_elem(L, E)</code>: <code>E</code> is the last element of list <code>L</code>.</p>
+<pre>
+?- last_elem([1,2,3], X).
+  X = 3.
+?- last_elem([3,2,X], 1).
+  X = 1.
+</pre>'''
+
+hint = {}
diff --git a/prolog/problems/lists/last_elem_2/sl.py b/prolog/problems/lists/last_elem_2/sl.py
new file mode 100644
index 0000000..c77ef57
--- /dev/null
+++ b/prolog/problems/lists/last_elem_2/sl.py
@@ -0,0 +1,21 @@
+name = 'last_elem/2'
+slug = 'Vrni zadnji element seznama'
+
+description = '''\
+<p><code>last_elem(L, E)</code>: <code>E</code> je zadnji element seznama <code>L</code>.</p>
+<pre>
+?- last_elem([1,2,3], X).
+  X = 3.
+?- last_elem([3,2,X], 1).
+  X = 1.
+</pre>
+'''
+
+plan = []
+
+hint = {
+    'timeout': '''\
+<p>Je morda na delu potencialno neskončna rekurzija? Kako se bo ustavila?</p>
+<p>Morda pa je kriv tudi manjkajoč, neustrezen ali preprosto nekompatibilen (s splošnim primerom) robni pogoj?</p>
+''',
+}