def test_delete_bst():
five = delete_node_bst.TreeNode(5)
two = delete_node_bst.TreeNode(2)
five.left = two
three = delete_node_bst.TreeNode(3)
two.right = three
four = delete_node_bst.TreeNode(4)
two.left = four
root = delete_node_bst.delete(five, 5)
assert root.val == 2
def test_delete_parent_node():
five = delete_node_bst.TreeNode(5)
two = delete_node_bst.TreeNode(2)
eight = delete_node_bst.TreeNode(8)
five.left = two
five.right = eight
three = delete_node_bst.TreeNode(3)
two.right = three
one = delete_node_bst.TreeNode(1)
two.left = one
nine = delete_node_bst.TreeNode(9)
eight.right = nine
six = delete_node_bst.TreeNode(6)
eight.left = six
seven = delete_node_bst.TreeNode(7)
six.right = seven
root = delete_node_bst.delete(five, 6)
assert root.val == 5
assert eight.left == seven
root = delete_node_bst.delete(five, 2)
assert root.val == 5
assert root.left == one
assert one.right == three
root = delete_node_bst.delete(five, 8)
assert root.val == 5
assert root.left.val == seven.val
assert seven.right.val == nine.val
def test_delete_leaf():
five = delete_node_bst.TreeNode(5)
two = delete_node_bst.TreeNode(2)
eight = delete_node_bst.TreeNode(8)
five.left = two
five.right = eight
three = delete_node_bst.TreeNode(3)
two.right = three
one = delete_node_bst.TreeNode(1)
two.left = one
nine = delete_node_bst.TreeNode(9)
eight.right = nine
six = delete_node_bst.TreeNode(6)
eight.left = six
seven = delete_node_bst.TreeNode(7)
six.right = seven
root = delete_node_bst.delete(five, 4)
assert root.val == 5
root = delete_node_bst.delete(five, 1)
assert root.val == 5
assert two.left is None
root = delete_node_bst.delete(five, 9)
assert root.val == 5
assert eight.right is None
root = delete_node_bst.delete(five, 3)
assert root.val == 5
assert two.right is None
def test_delete_root_bst():
five = delete_node_bst.TreeNode(5)
two = delete_node_bst.TreeNode(2)
eight = delete_node_bst.TreeNode(8)
five.left = two
five.right = eight
three = delete_node_bst.TreeNode(3)
two.right = three
four = delete_node_bst.TreeNode(4)
two.left = four
nine = delete_node_bst.TreeNode(9)
eight.right = nine
six = delete_node_bst.TreeNode(6)
eight.left = six
seven = delete_node_bst.TreeNode(7)
six.right = seven
root = delete_node_bst.delete(five, 5)
assert root.val == 6
assert eight.left.val == 7
assert root.right == eight
def test_delete():
one = delete_node_bst.TreeNode(1)
two = delete_node_bst.TreeNode(2)
one.right = two
root = delete_node_bst.delete(one, 1)
assert root.val == 2