def test_bt_stress(self):
from ch06.tree import BinaryTree
bt1 = BinaryTree()
N = 31
keys = list(range(N))
for k in keys:
bt1.insert(k)
self.assertEqual(list(range(k + 1)), list(bt1))
self.assertEqual(list(range(N)), list(bt1))
# remove in order
for k in keys:
bt1.remove(k)
self.assertEqual(list(range(k + 1, N)), list(bt1))
n = 0
for k in keys:
bt1.insert(k)
n += 1
self.assertEqual(list(range(k + 1)), list(bt1))
self.assertEqual(list(range(N)), list(bt1))
# remove in reverse order
for k in reversed(keys):
bt1.remove(k)
def test_stress_recreate(self):
from ch06.tree import BinaryTree
from ch06.challenge import tree_structure, recreate_tree
# create all subsets of 1..7
groups = [[1], [2], [3], [4], [5], [6], [7]]
for _ in range(6):
# Create complete tree with three levels.
for group in groups:
bt = BinaryTree()
for x in [4, 2, 6, 1, 3, 5, 7]:
bt.insert(x)
for s in group:
bt.remove(s)
s = tree_structure(bt.root)
n = recreate_tree(s, int) # recreate and convert to int
bt.root = n
# validate all values BUT in set are found
for i in range(1, 8):
if not i in group:
self.assertTrue(i in bt)
# expand deletions
new_groups = []
for group in groups:
for i in range(1, 8):
if not i in group:
new_groups.append(group + [i])
groups = new_groups
def test_bt_duplicates(self):
from ch06.tree import BinaryTree
bt1 = BinaryTree()
bt1.insert(5)
bt1.insert(5)
bt1.insert(4)
bt1.insert(5)
self.assertEqual([4, 5, 5, 5], list(bt1))
def test_count_rotations_avl(self):
from ch06.balanced import BinaryTree
bt1 = BinaryTree()
self.assertTrue(bt1.min() is None)
for i in [50, 30, 70, 20, 40, 60, 10, 45]:
bt1.insert(i)
self.assertEqual(50, bt1.root.value)
self.assertEqual(30, bt1.root.left.value)
self.assertEqual(20, bt1.root.left.left.value)
bt1.insert(5)
self.assertEqual(10, bt1.root.left.left.value) # rotate
def test_tree(self):
from ch06.tree import BinaryTree
bt1 = BinaryTree()
for n in [19, 14, 53, 3, 15, 26, 58]:
bt1.insert(n)
last = -1
while not bt1.is_empty():
m = bt1.min()
self.assertTrue(m > last)
last = m
bt1.remove(m)
def test_traversal(self):
from ch06.tree import BinaryTree
bt1 = BinaryTree()
bt1.insert(23)
bt1.insert(17)
bt1.insert(40)
bt1.insert(30)
total = 0
for v in bt1:
total += v
self.assertEqual(110, total)
def test_copy(self):
from ch06.tree import BinaryTree
bt1 = BinaryTree()
bt1.insert(23)
bt1.insert(17)
bt1.insert(40)
bt1.insert(30)
bt2 = bt1.copy()
total = 0
for v in bt2:
total += v
self.assertEqual(110, total)
def test_string_structure(self):
from ch06.tree import BinaryTree
from ch06.challenge import tree_structure
bt1 = BinaryTree()
self.assertFalse(99 in bt1)
bt1.insert(5)
bt1.insert(4)
bt1.insert(6)
bt1.insert(2)
bt1.insert(7)
bt1.insert(1)
bt1.insert(3)
# Prefix representation, with value first, then left and then right
self.assertEqual('(5,(4,(2,(1,,),(3,,)),),(6,,(7,,)))',
tree_structure(bt1.root))
def test_recreate_tree(self):
from ch06.challenge import recreate_tree, tree_structure
from ch06.tree import BinaryTree
root = recreate_tree('(19,,)')
self.assertEqual('19', root.value)
root = recreate_tree('(19,3,22)')
self.assertEqual('3', root.left.value)
self.assertEqual('22', root.right.value)
root = recreate_tree('(19,3,(22,21,24))')
self.assertEqual('3', root.left.value)
self.assertEqual('22', root.right.value)
self.assertEqual('21', root.right.left.value)
self.assertEqual('24', root.right.right.value)
root = recreate_tree('(26,,(29,,)')
self.assertEqual('26', root.value)
root = recreate_tree('(19,(14,(3,,),(15,,)),(53,(26,,(29,,)),(58,,)))')
self.assertEqual('19', root.value)
self.assertEqual(8, root.size())
# create and flatten again.
bt1 = BinaryTree()
bt1.insert(10)
bt1.insert(15)
bt1.insert(13)
bt1.insert(11)
s = tree_structure(bt1.root)
self.assertEqual('(10,,(15,(13,(11,,),),))', s)
n = recreate_tree(s)
self.assertEqual(s, tree_structure(n))
bt1 = BinaryTree()
bt1.insert(12)
bt1.insert(5)
s = tree_structure(bt1.root)
self.assertEqual('(12,(5,,),)', s)
n = recreate_tree(s)
self.assertEqual(s, tree_structure(n))
root = recreate_tree('(26,(23,,),)')
self.assertEqual('26', root.value)
root = recreate_tree('(23,5,(30,29,))')
self.assertEqual('23', root.value)
def test_val_height_valid_on_remove(self):
from ch06.balanced import BinaryTree
bt1 = BinaryTree()
bt1.insert(7)
self.assertEqual(7, bt1.min())
bt1.insert(4)
bt1.insert(10)
bt1.insert(8)
self.assertEqual(2, bt1.root.height)
self.assertEqual(4, bt1.root.size())
check_avl_property(bt1.root)
bt1.remove(7)
self.assertEqual(3, bt1.root.size())
self.assertEqual(1, bt1.root.height)
check_avl_property(bt1.root)
self.assertEqual(4, bt1.min())
self.assertTrue(4 in bt1)
self.assertTrue(10 in bt1)
self.assertTrue(8 in bt1)
self.assertFalse(7 in bt1)
def test_avl_stress(self):
from ch06.balanced import BinaryTree
bt1 = BinaryTree()
N = 63
keys = list(range(N))
for k in keys:
bt1.insert(k)
self.assertEqual(list(range(k + 1)), list(bt1))
check_avl_property(bt1.root)
self.assertEqual(list(range(N)), list(bt1))
# remove in order
for k in keys:
bt1.remove(k)
self.assertEqual(list(range(k + 1, N)), list(bt1))
check_avl_property(bt1.root)
for k in keys:
bt1.insert(k)
check_avl_property(bt1.root)
self.assertEqual(list(range(k + 1)), list(bt1))
self.assertEqual(list(range(N)), list(bt1))
# remove in reverse order
for k in reversed(keys):
bt1.remove(k)
check_avl_property(bt1.root)
self.assertEqual(list(range(k)), list(bt1))
for k in keys:
bt1.insert(k)
check_avl_property(bt1.root)
self.assertEqual(list(range(k + 1)), list(bt1))
self.assertEqual(list(range(N)), list(bt1))
# remove in random order. This revealed subtle defect in _remove_min()
shuffled = list(keys)
random.shuffle(shuffled)
for k in shuffled:
bt1.remove(k)
check_avl_property(bt1.root)
self.assertTrue(bt1.is_empty())
def test_bt(self):
from ch06.tree import BinaryTree
bt1 = BinaryTree()
self.assertTrue(bt1.remove(7) is None) # can work even when empty
self.assertTrue(bt1.min() is None)
bt1.insert(5)
self.assertTrue(5 in bt1)
bt1.insert(2)
self.assertEqual(5, bt1.root.value)
self.assertTrue(2 in bt1)
self.assertEqual([2, 5], list(bt1))
bt1.insert(1)
self.assertTrue(1 in bt1)
self.assertEqual([1, 2, 5], list(bt1))
def test_bt_remove(self):
from ch06.tree import BinaryTree
# delete with left child having right child
bt1 = BinaryTree()
bt1.insert(5)
bt1.insert(2)
bt1.insert(4)
bt1.insert(7)
self.assertEqual([2, 4, 5, 7], list(bt1))
bt1.remove(5)
self.assertEqual([2, 4, 7], list(bt1))
# delete with left child having only left child
bt2 = BinaryTree()
bt2.insert(5)
bt2.insert(2)
bt2.insert(1)
bt2.insert(7)
bt2.insert(8)
self.assertEqual([1, 2, 5, 7, 8], list(bt2))
bt2.remove(5)
self.assertEqual([1, 2, 7, 8], list(bt2))
# delete with no left child
bt3 = BinaryTree()
bt3.insert(5)
bt3.insert(7)
bt3.insert(8)
self.assertEqual([5, 7, 8], list(bt3))
bt3.remove(5)
self.assertEqual([7, 8], list(bt3))
# delete with no children
bt4 = BinaryTree()
bt4.insert(5)
self.assertEqual([5], list(bt4))
bt4.remove(5)
self.assertEqual([], list(bt4))