Added new exercises with recursion.

Added description for functions.

12 files changed, 388 insertions, 19 deletions

diff --git a/python/problems/recursion/distance/common.py b/python/problems/recursion/distance/common.py
new file mode 100644
index 0000000..f9a8c13
--- /dev/null
+++ b/python/problems/recursion/distance/common.py
@@ -0,0 +1,84 @@
+import re
+from python.util import has_token_sequence, string_almost_equal, \
+    string_contains_number, get_tokens, get_numbers, get_exception_desc, \
+    all_tokens, has_comprehension, has_loop, almost_equal, get_ast
+from server.hints import Hint
+
+id = 20811
+number = 11
+visible = True
+
+solution = '''\
+def distance(map, room1, room2):
+    if room1 not in map or room2 not in map:
+        return -1
+    if room1 == room2:
+        return 0
+    d1 = distance(map, map[room1][0], room2)
+    if d1 > -1:
+        return d1 + 1
+    d2 = distance(map, map[room1][1], room2)
+    if d2 > -1:
+        return d2 + 1
+    return -1
+'''
+
+hint_type = {
+    'final_hint': Hint('final_hint')
+}
+
+map = {0: [6, 3], 6: [5, 81], 3: [8, 24], 5: [2, 18],
+81: [None, None], 8: [42, None], 24: [63, 13], 2: [7, 27],
+18: [None, 35], 42: [None, 66], 63: [61, None], 13: [4, 12],
+7: [None, None], 27: [None, None], 35: [None, None], 66: [None, None],
+61: [None, None], 4: [None, None], 12: [None, None]}
+
+def test(python, code, aux_code=''):
+    func_name = 'distance'
+    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 = [
+        ((0, 42), 3),
+        ((0, 4), 4),
+        ((0, 5), 2),
+        ((0, 3), 1),
+        ((0, 0), 0),
+        ((42, 42), 0),
+        ((8, 66), 2),
+    ]
+    test_in = [('{}({}, {}, {})'.format(func_name, str(map), l[0][0], l[0][1]), None)
+               for l in in_out]
+    test_out = [l[1] for l in in_out]
+
+    answers = python(code=aux_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)):
+        res = ans[0]
+        corr = res == to
+        n_correct += corr
+        if not corr:
+            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, aux_code=''):
+    tokens = get_tokens(code)
+
+    # run one test first to see if there are any exceptions
+    answer = python(code=aux_code+code, inputs=[(None, None)], timeout=1.0)
+    exc = get_exception_desc(answer[0][3])
+    if exc: return exc
+
+    return None
diff --git a/python/problems/recursion/distance/en.py b/python/problems/recursion/distance/en.py
new file mode 100644
index 0000000..316859b
--- /dev/null
+++ b/python/problems/recursion/distance/en.py
@@ -0,0 +1,13 @@
+id = 20811
+name = 'Distance'
+
+description = '''\
+<p>(translation missing)</p>'''
+
+hint = {
+    'plan': '''\
+<p>(translation missing)</p>''',
+
+    'no_input_call': '''\
+<p>(translation missing)</p>''',
+}
diff --git a/python/problems/recursion/distance/sl.py b/python/problems/recursion/distance/sl.py
new file mode 100644
index 0000000..9cf9418
--- /dev/null
+++ b/python/problems/recursion/distance/sl.py
@@ -0,0 +1,31 @@
+import server
+mod = server.problems.load_language('python', 'sl')
+
+id = 20811
+name = 'Razdalja'
+
+description = '''\
+<p> <img src="[%@resource map.png%]"> </p>
+<p>
+Nadaljujmo z meglenim gorovjem. Napiši funkcijo
+<code>distance(map, start_room, ring_room)</code>,
+ki prejme zemljevid, številko začetne sobe in številko sobe s prstanom,
+kot rezultat pa vrne dolžino poti do nje. Če katerakoli od sob ne obstaja,
+vrni <code>-1</code>.
+Na gornjem zemljevidu je globina sobe 42 enaka 3. Zato:</p>
+<pre>
+>>> distance(map, 0, 42)
+3
+>>> distance(map, 0, 43)
+-1
+</pre>
+'''
+
+plan = []
+
+hint = {
+    'final_hint': ['''\
+<p>Program je pravilen! <br>
+</p>
+''']
+}
diff --git a/python/problems/recursion/find_sum/find_sum.py b/python/problems/recursion/find_sum/find_sum.py
deleted file mode 100644
index 85f472b..0000000
--- a/python/problems/recursion/find_sum/find_sum.py
+++ /dev/null
@@ -1,19 +0,0 @@
-def find_sum(xs, gs):
-    if gs < 0:
-        return False
-    if gs == 0:
-        return True
-    if not xs:
-        return False
-    return find_sum(xs[1:], gs-xs[0]) or find_sum(xs[1:], gs)
-
-print (find_sum([2,7,3,1,4], 10))
-print (find_sum([2,3,2,4], 10))
-print (find_sum([], 10))
-print (find_sum([1,2,3], 2))
-print (find_sum([1,2,3], 7))
-print (find_sum([2,7,3,1,4], 9))
-print (find_sum([2,7,3,2,4], 17))
-
-
-
diff --git a/python/problems/recursion/map.png b/python/problems/recursion/map.png
new file mode 100644
index 0000000..014d78e
--- /dev/null
+++ b/python/problems/recursion/map.png
diff --git a/python/problems/recursion/maxroom/common.py b/python/problems/recursion/maxroom/common.py
new file mode 100644
index 0000000..2709d76
--- /dev/null
+++ b/python/problems/recursion/maxroom/common.py
@@ -0,0 +1,73 @@
+import re
+from python.util import has_token_sequence, string_almost_equal, \
+    string_contains_number, get_tokens, get_numbers, get_exception_desc, \
+    all_tokens, has_comprehension, has_loop, almost_equal, get_ast
+from server.hints import Hint
+
+id = 20812
+number = 12
+visible = True
+
+solution = '''\
+def maxroom(map, room):
+    if room == None:
+        return -1
+    return max(room, maxroom(map, map[room][0]), maxroom(map, map[room][1]))
+'''
+
+hint_type = {
+    'final_hint': Hint('final_hint')
+}
+
+map = {0: [6, 3], 6: [5, 81], 3: [8, 24], 5: [2, 18],
+81: [None, None], 8: [42, None], 24: [63, 13], 2: [7, 27],
+18: [None, 35], 42: [None, 66], 63: [61, None], 13: [4, 12],
+7: [None, None], 27: [None, None], 35: [None, None], 66: [None, None],
+61: [None, None], 4: [None, None], 12: [None, None]}
+
+def test(python, code, aux_code=''):
+    func_name = 'maxroom'
+    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 = [
+        (0, 81),
+        (3, 66),
+        (63, 63),
+        (5, 35),
+    ]
+    test_in = [('{}({}, {})'.format(func_name, str(map), l[0]), None)
+               for l in in_out]
+    test_out = [l[1] for l in in_out]
+
+    answers = python(code=aux_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)):
+        res = ans[0]
+        corr = res == to
+        n_correct += corr
+        if not corr:
+            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, aux_code=''):
+    tokens = get_tokens(code)
+
+    # run one test first to see if there are any exceptions
+    answer = python(code=aux_code+code, inputs=[(None, None)], timeout=1.0)
+    exc = get_exception_desc(answer[0][3])
+    if exc: return exc
+
+    return None
diff --git a/python/problems/recursion/maxroom/en.py b/python/problems/recursion/maxroom/en.py
new file mode 100644
index 0000000..a876812
--- /dev/null
+++ b/python/problems/recursion/maxroom/en.py
@@ -0,0 +1,13 @@
+id = 20812
+name = 'Max room'
+
+description = '''\
+<p>(translation missing)</p>'''
+
+hint = {
+    'plan': '''\
+<p>(translation missing)</p>''',
+
+    'no_input_call': '''\
+<p>(translation missing)</p>''',
+}
diff --git a/python/problems/recursion/maxroom/sl.py b/python/problems/recursion/maxroom/sl.py
new file mode 100644
index 0000000..bfc5313
--- /dev/null
+++ b/python/problems/recursion/maxroom/sl.py
@@ -0,0 +1,29 @@
+import server
+mod = server.problems.load_language('python', 'sl')
+
+id = 20812
+name = 'Največja številka'
+
+description = '''\
+<p> <img src="[%@resource map.png%]"> </p>
+<p>
+Napiši funkcijo <code>maxroom(map, room)</code>, ki vrne največjo številko,
+v katero lahko pridemo, če se spustimo iz te sobe. </p>
+<pre>
+>>> maxroom(map, 0)
+81
+>>> maxroom(map, 3)
+66
+>>> maxroom(map, 12)
+12
+</pre>
+'''
+
+plan = []
+
+hint = {
+    'final_hint': ['''\
+<p>Program je pravilen! <br>
+</p>
+''']
+}
diff --git a/python/problems/recursion/where_to/common.py b/python/problems/recursion/where_to/common.py
new file mode 100644
index 0000000..55a9aed
--- /dev/null
+++ b/python/problems/recursion/where_to/common.py
@@ -0,0 +1,77 @@
+import re
+from python.util import has_token_sequence, string_almost_equal, \
+    string_contains_number, get_tokens, get_numbers, get_exception_desc, \
+    all_tokens, has_comprehension, has_loop, almost_equal, get_ast
+from server.hints import Hint
+
+id = 20810
+number = 10
+visible = True
+
+solution = '''\
+def where_to(map, room, path):
+    if path:
+        return where_to(map, map[room][path[0] == "R"], path[1:])
+    else:
+        return room
+'''
+
+hint_type = {
+    'final_hint': Hint('final_hint')
+}
+
+map = {0: [6, 3], 6: [5, 81], 3: [8, 24], 5: [2, 18],
+81: [None, None], 8: [42, None], 24: [63, 13], 2: [7, 27],
+18: [None, 35], 42: [None, 66], 63: [61, None], 13: [4, 12],
+7: [None, None], 27: [None, None], 35: [None, None], 66: [None, None],
+61: [None, None], 4: [None, None], 12: [None, None]}
+
+def test(python, code, aux_code=''):
+    func_name = 'where_to'
+    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 = [
+        ((0, "LLR"), 18),
+        ((0, "RRRR"), 12),
+        ((0, "L"), 6),
+        ((0, ""), 0),
+        ((0, "RLL"), 42),
+        ((0, "RRLL"), 61),
+        ((0, "LLLL"), 7),
+    ]
+    test_in = [('{}({}, {}, "{}")'.format(func_name, str(map), l[0][0], l[0][1]), None)
+               for l in in_out]
+    test_out = [l[1] for l in in_out]
+
+    answers = python(code=aux_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)):
+        res = ans[0]
+        corr = res == to
+        n_correct += corr
+        if not corr:
+            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, aux_code=''):
+    tokens = get_tokens(code)
+
+    # run one test first to see if there are any exceptions
+    answer = python(code=aux_code+code, inputs=[(None, None)], timeout=1.0)
+    exc = get_exception_desc(answer[0][3])
+    if exc: return exc
+
+    return None
diff --git a/python/problems/recursion/where_to/en.py b/python/problems/recursion/where_to/en.py
new file mode 100644
index 0000000..df43164
--- /dev/null
+++ b/python/problems/recursion/where_to/en.py
@@ -0,0 +1,13 @@
+id = 20810
+name = 'Where to'
+
+description = '''\
+<p>(translation missing)</p>'''
+
+hint = {
+    'plan': '''\
+<p>(translation missing)</p>''',
+
+    'no_input_call': '''\
+<p>(translation missing)</p>''',
+}
diff --git a/python/problems/recursion/where_to/map.png b/python/problems/recursion/where_to/map.png
new file mode 100644
index 0000000..014d78e
--- /dev/null
+++ b/python/problems/recursion/where_to/map.png
diff --git a/python/problems/recursion/where_to/sl.py b/python/problems/recursion/where_to/sl.py
new file mode 100644
index 0000000..365d7cd
--- /dev/null
+++ b/python/problems/recursion/where_to/sl.py
@@ -0,0 +1,55 @@
+import server
+mod = server.problems.load_language('python', 'sl')
+
+id = 20810
+name = 'Kam?'
+
+description = '''\
+<p>
+od Meglenim gorovjem je, kot nekateri vedo že dolgo,
+nekateri pa so morali čakati na film, cel labirint votlin.
+Bilbu bi bilo veliko lažje, če bi imel zemljevid. Mi ga imamo.
+
+Zemljevid lahko shranimo tudi v obliki slovarja,
+v katerem so ključi številke sob, vrednosti pa sobe,
+v katere pridemo po levi in po desni poti.
+Kadar kakšne poti ni, je ustrezni element enak None.</p>
+
+<img src="[%@resource map.png%]">
+
+<pre>
+map = {0: [6, 3], 6: [5, 81], 3: [8, 24], 5: [2, 18],
+81: [None, None], 8: [42, None], 24: [63, 13], 2: [7, 27],
+18: [None, 35], 42: [None, 66], 63: [61, None], 13: [4, 12],
+7: [None, None], 27: [None, None], 35: [None, None], 66: [None, None],
+61: [None, None], 4: [None, None], 12: [None, None]}</pre>
+
+<p>Napiši funkcijo <code>where_to(map, room, path)</code>,
+ki kot argument prejme zemljevid (npr. zgornji slovar),
+začetno sobo (ta bo vedno 0, a to naj te ne moti) in pot (<code>path</code>),
+podano kot zaporedje znakov <code>L</code> in <code>R</code> (levo in desno).
+Kot rezultat mora vrniti sobo, v katero pelje podana pot.</p>
+
+<pre>
+>>> where_to(map, 0, "LLR")
+18
+>>> where_to(map, 0, "RRRR")
+12
+>>> where_to(map, 0, "L")
+6
+>>> where_to(map, 0, "")
+0
+</pre>
+
+<p> Predpostaviti smeš, da je pot pravilna in se nikoli ne odpravi v hodnik,
+ki ga ni.</p>
+'''
+
+plan = []
+
+hint = {
+    'final_hint': ['''\
+<p>Program je pravilen! <br>
+</p>
+''']
+}