def test_pq1(self):
pq = MinPQ()
self.assertTrue(pq.is_empty())
for i in reversed(range(5)):
print("pq.insert(", i, ")")
pq.insert(i)
self.assertEqual(pq.size(), 5)
self.assertFalse(pq.is_empty())
self.assertEqual(pq.min(), 0)
def test_pq2(self):
pq = MinPQ()
pq2 = MinPQ()
self.assertEqual(pq2 == pq, True)
pq.insert(0)
pq.insert(0)
pq.insert(1)
self.assertEqual(pq.min(), 0)
self.assertEqual(pq.del_min(), 0)
self.assertEqual(pq.del_min(), 0)
self.assertEqual(pq.del_min(), 1)
def test_min_pq(self):
minq = MinPQ([5, 4, 3, 2, 1, 0])
minq2 = MinPQ()
minq2.insert(0)
minq2.insert(1)
self.assertEqual(minq2.capacity, 2)
minq2.insert(2)
self.assertEqual(minq2.capacity, 4)
minq2.insert(3)
minq2.insert(4)
minq2.insert(5)
self.assertEqual(minq2.min(), 0)
minq2.del_min()
self.assertEqual(minq2.min(), 1)
self.assertEqual(minq2.size(), 5)
minq2.del_min()
minq2.del_min()
self.assertEqual(minq2.capacity, 8)
minq2.del_min()
self.assertEqual(minq2.capacity, 4)
minq2.del_min()
minq2.del_min()
self.assertRaises(IndexError, minq2.del_min)
def test_pq(self):
pq = MinPQ([3, 10, 231, 5])
self.assertEqual(pq.is_empty(), False)
self.assertEqual(pq.size(), 4)
self.assertEqual(pq.capacity, 4)
self.assertEqual(pq.min(), 3)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 5)
self.assertEqual(pq.del_min(), 10)
self.assertEqual(pq.del_min(), 231)
self.assertRaises(IndexError, pq.min)
self.assertRaises(IndexError, pq.del_min)
self.assertEqual(pq.is_empty(), True)
self.assertEqual(pq.num_items, 0)
def test_pq3(self):
pq = MinPQ()
self.assertTrue(pq.is_empty())
i = 1
print("pq.insert(", i, ")")
pq.insert(i)
self.assertEqual(pq.min(), 1)
i = 5
print("pq.insert(", i, ")")
pq.insert(i)
self.assertEqual(pq.min(), 1)
i = 3
print("pq.insert(", i, ")")
pq.insert(i)
self.assertEqual(pq.del_min(), 1)
i = 4
print("pq.insert(", i, ")")
pq.insert(i)
self.assertEqual(pq.min(), 3)
i = 2
print("pq.insert(", i, ")")
pq.insert(i)
self.assertEqual(pq.min(), 2)
self.assertEqual(pq.del_min(), 2)
def test_2(self):
pq = MinPQ([5, 4, 3, 2, 1])
self.assertEqual(pq.size(), 5)
self.assertTrue(pq.capacity == 5)
self.assertTrue(pq.capacity == pq.num_items)
self.assertTrue(pq.arr == [1, 2, 3, 5, 4])
self.assertEqual(pq.min(), 1)
self.assertEqual(pq.del_min(), 1)
self.assertEqual(pq.del_min(), 2)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 4)
self.assertEqual(pq.del_min(), 5)
self.assertTrue(pq.capacity == 2)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
def test_1(self):
pq = MinPQ()
pq.insert(5)
pq.insert(3)
self.assertEqual(pq.capacity, 2)
pq.insert(6)
self.assertEqual(pq.size(), 3)
self.assertTrue(pq.capacity == 4)
self.assertEqual(pq.min(), 3)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 5)
self.assertEqual(pq.del_min(), 6)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
self.assertTrue(pq.capacity == 2)
def test_use_case_one(self):
""" Implementation of use case 1 as outlined in lab instructions"""
pq_test = MinPQ()
pq_test.insert(5)
pq_test.insert(3)
self.assertTrue(pq_test.capacity == 2)
pq_test.insert(6)
self.assertEqual(3, pq_test.size())
self.assertEqual(3, pq_test.min())
self.assertEqual(3, pq_test.del_min())
self.assertEqual(5, pq_test.del_min())
self.assertEqual(6, pq_test.del_min())
self.assertEqual(0, pq_test.size())
self.assertTrue(pq_test.is_empty())
self.assertEqual(2, pq_test.capacity)
def test_pq4(self):
arr = [5, 2, 3, 4, 1]
print(arr)
pq = MinPQ(arr)
print("pq.heapify(",arr,")")
self.assertEqual(pq.size(), 5)
self.assertEqual(pq.capacity, 5)
self.assertFalse(pq.is_empty())
self.assertEqual(pq.min(), 1)
self.assertEqual(pq.del_min(), 1)
self.assertEqual(pq.del_min(), 2)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 4)
self.assertEqual(pq.del_min(), 5)
self.assertTrue(pq.is_empty())
def test_use_case_two(self):
""" Implementation of use case 2 as outlined in lab instructions"""
pq_test = MinPQ([5, 4, 3, 2, 1])
self.assertEqual(5, pq_test.size())
self.assertEqual(5, pq_test.capacity)
self.assertEqual(pq_test.num_items, pq_test.capacity)
self.assertTrue(pq_test.arr == [1, 2, 3, 5, 4])
self.assertEqual(1, pq_test.min())
self.assertEqual(1, pq_test.del_min())
self.assertEqual(2, pq_test.del_min())
self.assertFalse(pq_test.is_empty())
self.assertEqual(3, pq_test.del_min())
self.assertEqual(4, pq_test.del_min())
self.assertEqual(5, pq_test.del_min())
self.assertEqual(2, pq_test.capacity)
self.assertEqual(0, pq_test.size())
self.assertTrue(pq_test.is_empty())
def create_huff_tree(list_of_freqs):
"""returns the root node of a Huffman Tree
"""
huff_tree = []
for idx in range(len(list_of_freqs)):
if list_of_freqs[idx] != 0:
huff_tree.append(HuffmanNode(list_of_freqs[idx], chr(idx)))
huff_arr = MinPQ()
huff_arr.heapify(huff_tree)
while huff_arr.num_items > 1:
node1 = huff_arr.del_min()
node2 = huff_arr.del_min()
freq = node1.freq + node2.freq
char = min(node1.char, node2.char)
new_huff_node = HuffmanNode(freq, char)
new_huff_node.left = node1
new_huff_node.right = node2
huff_arr.insert(new_huff_node)
return huff_arr.min()
def create_huff_tree(list_of_freqs):
"""Creates a huffman tree given a list of character frequencies.
Arguments:
list_of_freqs (list): List of character frequencies from cnt_freq()
Returns:
The root node of the huffman tree created from the list of frequencies
"""
pq_arr = []
for char, freq in enumerate(list_of_freqs):
if freq > 0:
pq_arr.append(HuffmanNode(chr(char), freq, None, None))
min_pq = MinPQ(pq_arr)
while min_pq.size() > 1:
left = min_pq.del_min()
right = min_pq.del_min()
min_char = min(left.char, right.char)
parent_node = HuffmanNode(min_char, left.freq + right.freq, left, right)
min_pq.insert(parent_node)
return min_pq.min()
class MinPQTests(unittest.TestCase):
def setUp(self):
self.pq1 = MinPQ()
self.pq2 = MinPQ()
def test_eq_repr(self):
self.assertEqual(repr(self.pq1), 'MinPQ([None, None])')
self.assertEqual(self.pq1, self.pq2)
self.assertEqual(self.pq1.size(), 0)
self.assertEqual(self.pq2.size(), 0)
self.pq1.insert(0)
self.pq1.insert(4)
self.pq1.insert(3)
self.pq2.insert(4)
self.pq2.insert(3)
self.pq2.insert(0)
self.assertEqual(repr(self.pq1), 'MinPQ([0, 4, 3, None])')
self.assertEqual(self.pq1.size(), 3)
self.assertEqual(self.pq1.min(), 0)
self.assertEqual(self.pq1, self.pq2)
def test_heapify(self):
pq = MinPQ([9, 6, 5, 2, 3])
self.assertEqual(pq.arr, [2, 3, 5, 6, 9])
pq = MinPQ([6, 3, 7, 2, 8, 1])
self.assertEqual(pq.arr, [1, 2, 6, 3, 8, 7])
pq = MinPQ([1, 3, 6, 8])
self.assertEqual(pq.arr, [1, 3, 6, 8])
def test_insert_del_size(self):
self.assertRaises(IndexError, self.pq1.del_min)
self.pq1.insert(1)
self.assertEqual(self.pq1.size(), 1)
self.assertEqual(self.pq1.arr, [1, None])
self.pq1.insert(6)
self.assertEqual(self.pq1.size(), 2)
self.assertEqual(self.pq1.arr, [1, 6])
self.pq1.insert(5)
self.assertEqual(self.pq1.size(), 3)
self.assertEqual(self.pq1.arr, [1, 6, 5, None])
self.assertEqual(self.pq1.del_min(), 1)
self.assertEqual(self.pq1.arr, [5, 6, None, None])
self.pq1.insert(1)
self.assertEqual(self.pq1.arr, [1, 6, 5, None])
def test_1(self):
pq = MinPQ()
pq.insert(5)
pq.insert(3)
self.assertEqual(pq.capacity, 2)
pq.insert(6)
self.assertEqual(pq.size(), 3)
self.assertTrue(pq.capacity == 4)
self.assertEqual(pq.min(), 3)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 5)
self.assertEqual(pq.del_min(), 6)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
self.assertTrue(pq.capacity == 2)
def test_2(self):
pq = MinPQ([5, 4, 3, 2, 1])
self.assertEqual(pq.size(), 5)
self.assertTrue(pq.capacity == 5)
self.assertTrue(pq.capacity == pq.num_items)
self.assertTrue(pq.arr == [1, 2, 3, 5, 4])
self.assertEqual(pq.min(), 1)
self.assertEqual(pq.del_min(), 1)
self.assertEqual(pq.del_min(), 2)
self.assertEqual(pq.del_min(), 3)
self.assertEqual(pq.del_min(), 4)
self.assertEqual(pq.del_min(), 5)
self.assertTrue(pq.capacity == 2)
self.assertEqual(pq.size(), 0)
self.assertTrue(pq.is_empty())
