1 files changed, 98 insertions, 0 deletions
diff --git a/python/problems/introduction/average/common.py b/python/problems/introduction/average/common.py
new file mode 100644
index 0000000..37d5315
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+++ b/python/problems/introduction/average/common.py
@@ -0,0 +1,98 @@
+# coding=utf-8
+
+from python.util import has_token_sequence, string_almost_equal
+from server.hints import Hint, HintSequence
+
+id = 189
+group = 'introduction'
+number = 2
+visible = True
+
+solution = '''\
+a = float(input('Ocena [Ana]? '))
+b = float(input('Ocena [Benjamin]? '))
+c = float(input('Ocena [Cilka]? '))
+print('Povpre?je:', (a + b + c) / 3)
+print('Srednja vrednost:', a + b + c - min(a, b, c) - max( a, b, c))
+'''
+
+hint_type = {
+    'plan': Hint('plan'),
+    'eval_expression': Hint('eval_expression'),
+    'name_error': HintSequence('name_error', 4),
+    'unsupported_operand': HintSequence('unsupported_operand', 4),
+    'error': HintSequence('error', 2),
+    'radians': HintSequence('radians', 3),
+    'printing': Hint('printing'),
+}
+
+
+
+def test(python, code):
+    # List of inputs: (expression to eval, stdin).
+    test_in = [
+        (None, '2\n4\n5\n'),
+        (None, '1\n1\n4\n'),
+        (None, '2\n5\n1\n'),
+        (None, '3\n1\n1\n'),
+        (None, '5\n1\n5\n'),
+    ]
+
+    test_out = [
+        [3.67, 4],
+        [2, 1],
+        [2.67, 2],
+        [1.67, 1],
+        [3.67, 5]
+    ]
+
+    # List of outputs: (expression result, stdout, stderr, exception).
+    answers = python(code=code, inputs=test_in, timeout=1.0)
+    outputs = [ans[1] for ans in answers]
+
+    n_correct = 0
+    for output, c in zip(outputs, test_out):
+        if string_almost_equal(output, c[0]) and \
+           string_almost_equal(output, c[1]):
+            n_correct += 1
+    return n_correct, len(test_in)
+
+def hint(python, code):
+    # run one test first to see if there are any exceptions
+    test_in = [(None, '1\n1\n4\n')]
+    answer = python(code=code, inputs=test_in, timeout=1.0)
+    exc = answer[0][3]
+    # if have an exception!
+    if exc:
+        if 'NameError' in exc:
+            return [{'id':'name_error', 'args': {'message': exc}}]
+        elif 'TypeError' in exc:
+            return [{'id':'type_error', 'args': {'message': exc}}]
+        else:
+            return [{'id':'error', 'args': {'message': exc}}]
+
+    # show plan if student is lost
+    # a) empty progam
+    # b) there is not input (we can do it here, since we have no input hint)
+    if not code or (not has_token_sequence(code, ['input'])):
+        return [{'id': 'plan'}]
+
+    # Help to compute average (if /3 is not program)
+    if not has_token_sequence(code, ['/', '3']):
+        return [{'id': 'average'}]
+
+    # If student is not using functions min or max, then he is
+    # not computing median in the right way
+    if not has_token_sequence(code, ['min']) or \
+       not has_token_sequence(code, ['max']):
+        return [{'id': 'median'}]
+
+    # program is working correctly for mean but not for median
+    if '2' in answer[0][1] and '1' not in answer[0][1]:
+        return [{'id': 'median'}]
+
+    # student is not using print function
+    if not has_token_sequence(code, ['print']):
+        return [{'id' : 'printing'}]
+
+    return None