def test_extract_min(self):
""" Makes sure that the heap produces min values and that
the heap property is preserved.
Given the following heap:
(4)
/ \
(4) (8)
/ \ / \
(9) (4) (12) (9)
/ \
(11) (13)
"""
data = [4, 4, 8, 9, 4, 12, 9, 11, 13]
h = Heap(data)
min_key = h.extract_min()
self.assertEqual(min_key, 4, 'should extract the min value')
self.assertTrue(Heap.is_heap(data), 'should still hold the heap property')
min_key = h.extract_min()
self.assertEqual(min_key, 4, 'should extract the min value')
self.assertTrue(Heap.is_heap(data), 'should still hold the heap property')
min_key = h.extract_min()
self.assertEqual(min_key, 4, 'should extract the min value')
self.assertTrue(Heap.is_heap(data), 'should still hold the heap property')
def test_extract_min(self):
""" Makes sure that the heap produces min values and that
the heap property is preserved.
Given the following heap:
(4)
/ \
(4) (8)
/ \ / \
(9) (4) (12) (9)
/ \
(11) (13)
"""
data = [4, 4, 8, 9, 4, 12, 9, 11, 13]
h = Heap(data)
min_key = h.extract_min()
self.assertEqual(min_key, 4, 'should extract the min value')
self.assertTrue(Heap.is_heap(data),
'should still hold the heap property')
min_key = h.extract_min()
self.assertEqual(min_key, 4, 'should extract the min value')
self.assertTrue(Heap.is_heap(data),
'should still hold the heap property')
min_key = h.extract_min()
self.assertEqual(min_key, 4, 'should extract the min value')
self.assertTrue(Heap.is_heap(data),
'should still hold the heap property')
def test_static_is_heap(self):
""" Tests static method is_heap if it can correctly verify if a
list of elements preserves the heap property.
"""
good = [4, 4, 8, 9, 4, 12, 9, 11, 13]
bad = [1,2,3,114,5,6,7,8,9,10]
self.assertTrue(Heap.is_heap(good), 'should hold the heap property')
self.assertFalse(Heap.is_heap(bad), 'should not hold the heap property')
def test_static_is_heap(self):
""" Tests static method is_heap if it can correctly verify if a
list of elements preserves the heap property.
"""
good = [4, 4, 8, 9, 4, 12, 9, 11, 13]
bad = [1, 2, 3, 114, 5, 6, 7, 8, 9, 10]
self.assertTrue(Heap.is_heap(good), 'should hold the heap property')
self.assertFalse(Heap.is_heap(bad),
'should not hold the heap property')
def test_bubble_down(self):
h = Heap([])
h.data = [3, 2, 4]
new_index = h.bubble_down(0)
self.assertTrue(Heap.is_heap(h.data), 'should maintain the heap prop')
self.assertEqual(h.data, [2,3,4], 'should have reorganized the heap')
self.assertEqual(new_index, 1, 'should return the correct new index')
def test_bubble_down(self):
h = Heap([])
h.data = [3, 2, 4]
new_index = h.bubble_down(0)
self.assertTrue(Heap.is_heap(h.data), 'should maintain the heap prop')
self.assertEqual(h.data, [2, 3, 4], 'should have reorganized the heap')
self.assertEqual(new_index, 1, 'should return the correct new index')
def test_insert(self):
""" Test that adding an element preserves the heap property.
Given the following heap:
(4)
/ \
(4) (8)
/ \ / \
(9) (4) (12) (9)
/ \
(11) (13)
"""
data = [4, 4, 8, 9, 4, 12, 9, 11, 13]
h = Heap(data)
h.insert(7)
self.assertTrue(Heap.is_heap(h.data), 'should still be a heap')
h.insert(10)
self.assertTrue(Heap.is_heap(h.data), 'should still be a heap')
h.insert(5)
self.assertTrue(Heap.is_heap(h.data), 'should still be a heap')
def test_insert(self):
""" Test that adding an element preserves the heap property.
Given the following heap:
(4)
/ \
(4) (8)
/ \ / \
(9) (4) (12) (9)
/ \
(11) (13)
"""
data = [4, 4, 8, 9, 4, 12, 9, 11, 13]
h = Heap(data)
h.insert(7)
self.assertTrue(Heap.is_heap(h.data), 'should still be a heap')
h.insert(10)
self.assertTrue(Heap.is_heap(h.data), 'should still be a heap')
h.insert(5)
self.assertTrue(Heap.is_heap(h.data), 'should still be a heap')
def test_remove(self):
""" Test the removal of a key from the middle of the heap.
Given the following heap:
(4)
/ \
(4) (8)
/ \ / \
(9) (4) (12) (9)
/ \
(11) (13)
"""
data = [4, 4, 8, 9, 4, 12, 9, 11, 13]
h = Heap(data)
h.remove(2)
self.assertTrue(Heap.is_heap(data), 'should preserve heap property')
self.assertNotIn(8, h.data, 'the value corresponding to the index was removed')
def test_remove(self):
""" Test the removal of a key from the middle of the heap.
Given the following heap:
(4)
/ \
(4) (8)
/ \ / \
(9) (4) (12) (9)
/ \
(11) (13)
"""
data = [4, 4, 8, 9, 4, 12, 9, 11, 13]
h = Heap(data)
h.remove(2)
self.assertTrue(Heap.is_heap(data), 'should preserve heap property')
self.assertNotIn(8, h.data,
'the value corresponding to the index was removed')
def test_remove_if_index_is_last(self):
data = [3, 4, 5]
h = Heap(data)
h.remove(2)
self.assertEqual(h.data, [3, 4], 'should remove the last leaf')
self.assertTrue(Heap.is_heap(h.data), 'should maintain heap invariant')
def test_static_heapify(self):
data = [8,2,6,3,1,2,9,5,3,7,4]
h = Heap.heapify(data)
self.assertTrue(Heap.is_heap(data), 'should preserve heap property')
def test_remove_if_one_element(self):
data = [3]
h = Heap(data)
h.remove(0)
self.assertEqual(h.data, [], 'should remove the only elem in heap')
self.assertTrue(Heap.is_heap(h.data), 'should maintain heap invariant')
def test_static_heapify(self):
data = [8, 2, 6, 3, 1, 2, 9, 5, 3, 7, 4]
h = Heap.heapify(data)
self.assertTrue(Heap.is_heap(data), 'should preserve heap property')
def test_remove_if_one_element(self):
data = [3]
h = Heap(data)
h.remove(0)
self.assertEqual(h.data, [], 'should remove the only elem in heap')
self.assertTrue(Heap.is_heap(h.data), 'should maintain heap invariant')
def test_remove_if_index_is_last(self):
data = [3, 4, 5]
h = Heap(data)
h.remove(2)
self.assertEqual(h.data, [3, 4], 'should remove the last leaf')
self.assertTrue(Heap.is_heap(h.data), 'should maintain heap invariant')
def test_remove_if_index_is_root(self):
data = [3, 4, 5]
h = Heap(data)
h.remove(0)
self.assertEqual(h.data, [4, 5], 'should remove the root')
self.assertTrue(Heap.is_heap(h.data), 'should maintain heap invariant')
def test_remove_if_index_is_root(self):
data = [3, 4, 5]
h = Heap(data)
h.remove(0)
self.assertEqual(h.data, [4,5], 'should remove the root')
self.assertTrue(Heap.is_heap(h.data), 'should maintain heap invariant')
