1 files changed, 71 insertions, 0 deletions
diff --git a/python/problems/dictionaries/transactions/common.py b/python/problems/dictionaries/transactions/common.py
new file mode 100644
index 0000000..66d6387
--- /dev/null
+++ b/python/problems/dictionaries/transactions/common.py
@@ -0,0 +1,71 @@
+import re
+from python.util import has_token_sequence, string_almost_equal, \
+    string_contains_number, get_tokens, get_numbers, get_exception_desc
+from server.hints import Hint
+
+id = 20605
+number = 4
+visible = True
+
+solution = '''\
+def transactions(start, trans):
+    state = dict(start)
+    for fr, to, amount in trans:
+        state[fr] -= amount
+        state[to] += amount
+    most = None # could use -1, however all can be in debt
+    for who, amount in state.items():
+        if most is None or amount > most:
+            most, richest = amount, who
+    return richest
+'''
+
+hint_type = {
+    'final_hint': Hint('final_hint')
+}
+
+def test(python, code):
+    func_name = 'transactions'
+    tokens = get_tokens(code)
+    if not has_token_sequence(tokens, ['def', func_name]):
+        return False, [{'id' : 'no_func_name', 'args' : {'func_name' : func_name}}]
+
+    in_out = [
+        (([("Ana", 0), ("Berta", 1)], [("Berta", "Ana", 1)]), "Ana"),
+        (([("Ana", 0), ("Berta", 1)], []), "Berta"),
+        (([("Ana", 3), ("Berta", 2)], [("Berta", "Berta", 3)]), "Ana"),
+        (([("Ana", 4), ("Berta", 8), ("Cilka", 10)],
+          [("Cilka", "Ana", 3), ("Cilka", "Ana", 2), ("Ana", "Berta", 2)]),
+         "Berta"),
+    ]
+
+    test_in = [('{0}{1}'.format(func_name, str(l[0])), None) for l in in_out]
+    test_out = [l[1] for l in in_out]
+
+    answers = python(code=code, inputs=test_in, timeout=1.0)
+    n_correct = 0
+    tin, tout = None, None
+    for i, (ans, to) in enumerate(zip(answers, test_out)):
+        n_correct += ans[0] == to
+        if ans[0] != to:
+            tin = test_in[i][0]
+            tout = to
+
+    passed = n_correct == len(test_in)
+    hints = [{'id': 'test_results', 'args': {'passed': n_correct, 'total': len(test_in)}}]
+    if tin:
+        hints.append({'id': 'problematic_test_case', 'args': {'testin': str(tin), 'testout': str(tout)}})
+    if passed:
+        hints.append({'id': 'final_hint'})
+    return passed, hints
+
+
+def hint(python, code):
+    tokens = get_tokens(code)
+
+    # run one test first to see if there are any exceptions
+    answer = python(code=code, inputs=[(None, None)], timeout=1.0)
+    exc = get_exception_desc(answer[0][3])
+    if exc: return exc
+
+    return None