class TestMinHeap(unittest.TestCase):
def setUp(self):
self.heap = MinHeap()
def test_basic_initialization_and_repr(self):
self.assertEqual(repr(self.heap), '[]')
def test_insert(self):
self.heap.insert(4)
self.assertEqual(repr(self.heap), '[4]')
self.assertEqual(self.heap.size, 1)
self.heap.insert(4)
self.assertEqual(repr(self.heap), '[4, 4]')
self.assertEqual(self.heap.size, 2)
self.heap.insert(6)
self.assertEqual(repr(self.heap), '[4, 4, 6]')
self.assertEqual(self.heap.size, 3)
self.heap.insert(1)
self.assertEqual(repr(self.heap), '[1, 4, 6, 4]')
self.assertEqual(self.heap.size, 4)
self.heap.insert(3)
self.assertEqual(repr(self.heap), '[1, 3, 6, 4, 4]')
self.assertEqual(self.heap.size, 5)
def test_get_min(self):
self.assertEqual(self.heap.get_min(), None)
self.heap.insert(4)
self.assertEqual(self.heap.get_min(), 4)
self.heap.insert(7)
self.assertEqual(self.heap.get_min(), 4)
self.heap.insert(2)
self.assertEqual(self.heap.get_min(), 2)
self.heap.insert(-1)
self.assertEqual(self.heap.get_min(), -1)
def test_extract_min(self):
self.heap.insert(4)
self.heap.insert(5)
self.heap.insert(7)
self.heap.insert(2)
self.heap.insert(-1)
self.assertEqual(self.heap.extract_min(), -1)
self.assertEqual(self.heap.extract_min(), 2)
self.assertEqual(self.heap.extract_min(), 4)
self.assertEqual(self.heap.extract_min(), 5)
self.assertEqual(self.heap.extract_min(), 7)
self.assertEqual(self.heap.extract_min(), None)
def test_build_heap(self):
self.heap.build_heap([4, 4, 6, 1, 3])
self.assertEqual(repr(self.heap), '[1, 3, 6, 4, 4]')
def test_insert_and_get_many_random_items(self):
heap = MinHeap()
items = random.sample(range(1000), 50)
for index, item in enumerate(items):
heap.insert(item)
assert heap.size() == index + 1
min_item = min(items[: index + 1])
assert heap.get_min() == min_item
assert heap.size() == len(items)
def test_insert_and_get_many_items(self):
heap = MinHeap()
items = [9, 25, 86, 3, 29, 5, 55]
for index, item in enumerate(items):
heap.insert(item)
assert heap.size() == index + 1
min_item = min(items[: index + 1])
assert heap.get_min() == min_item
assert heap.size() == len(items)
assert heap.items == [3, 9, 5, 25, 29, 86, 55]
def test_insert_and_get_one_item(self):
heap = MinHeap()
heap.insert(5)
assert heap.size() == 1
assert heap.get_min() == 5
assert heap.items == [5]
def test_get_min_on_empty_heap(self):
heap = MinHeap()
with self.assertRaises(ValueError):
heap.get_min()
