def test_even_length_dfa(self):
even_length_dfa = Dfa(2, get_alphabet(), 0, 0)
even_length_dfa.add_transition(0, 1, '0')
even_length_dfa.add_transition(0, 1, '1')
even_length_dfa.add_transition(1, 0, '0')
even_length_dfa.add_transition(1, 0, '1')
for i in range(1000):
s: str = get_random_string()
self.assertEqual(not bool(len(s) % 2), even_length_dfa.accepts(s))
self.assertEqual(True, even_length_dfa.accepts(''))
def test_odd_length_dfa(self):
odd_length_dfa = Dfa(2, get_alphabet(), 0, 1)
odd_length_dfa.add_transition(0, 1, '0')
odd_length_dfa.add_transition(0, 1, '1')
odd_length_dfa.add_transition(1, 0, '0')
odd_length_dfa.add_transition(1, 0, '1')
for i in range(1000):
s: str = get_random_string()
self.assertEqual(bool(len(s) % 2), odd_length_dfa.accepts(s))
self.assertEqual(False, odd_length_dfa.accepts(''))
def test_empty_dfa(self):
d = Dfa(1, get_alphabet(), 0)
d.add_transition(0, 0, '0')
d.add_transition(0, 0, '1')
for i in range(1000):
self.assertEqual(False, d.accepts(get_random_string()))
self.assertEqual(False, d.accepts(''))
def test_odd_0s(self):
d = Dfa(2, get_alphabet(), 0, 1)
d.add_transition(0, 0, '1')
d.add_transition(0, 1, '0')
d.add_transition(1, 0, '0')
d.add_transition(1, 1, '1')
for i in range(1000):
s: str = get_random_string()
j: int = 0
for symbol in s:
if symbol == '0':
j += 1
self.assertEqual(bool(j % 2), d.accepts(s))
def test_three0_in_row(self):
d = Dfa(4, get_alphabet(), 0, 3)
d.add_transition(0, 0, '1')
d.add_transition(0, 1, '0')
d.add_transition(1, 0, '1')
d.add_transition(1, 2, '0')
d.add_transition(2, 0, '1')
d.add_transition(2, 3, '0')
d.add_transition(3, 3, '0')
d.add_transition(3, 3, '1')
for i in range(1000):
s: str = get_random_string()
self.assertEqual('000' in s, d.accepts(s))
def test_even_0_or_len(self):
d = Dfa(4, get_alphabet(), 0, 0, 1, 2)
d.add_transition(0, 3, '0')
d.add_transition(0, 1, '1')
d.add_transition(1, 2, '0')
d.add_transition(1, 0, '1')
d.add_transition(2, 1, '0')
d.add_transition(2, 3, '1')
d.add_transition(3, 0, '0')
d.add_transition(3, 2, '1')
for i in range(1000):
s: str = get_random_string()
ctr: int = s.count('0')
expected: bool = bool(not (ctr % 2)) or bool(not (len(s) % 2))
self.assertEqual(expected, d.accepts(s))