def test_rotate_left():
'''Test left rotation on the root of a tree.'''
# A full binary search tree.
tree = build_tree([4, 2, 1, 3, 6, 5, 7])
# tree.display()
# The expected result.
target_tree = build_tree([6, 4, 2, 1, 3, 5, 7])
# target_tree.display()
assert target_tree.root.parent == None, \
'tree.parent should have been None.'
assert tree.root.parent == None, 'tree.parent should have been None.'
assert bst.size(tree.root) == 7, 'tree size should be 7.'
assert bst.is_valid_tree(tree.root), 'Valid tree was marked as invalid.'
bst.rotate_left(tree, tree.root)
assert bst.size(tree.root) == 7, 'tree size should be 7.'
assert bst.is_valid_tree(tree.root), 'Valid tree was marked as invalid.'
assert tree.root.parent == None, 'tree.parent should have been None.'
assert tree == target_tree, '__eq__ did not work properly.'
assert not (tree != target_tree), '__ne__ did not work properly.'
def test_rotate_left(self):
'''Test left rotation on the root of a tree.'''
# A full binary search tree.
tree = build_tree([4, 2, 1, 3, 6, 5, 7])
#tree.display()
# The expected result.
target_tree = build_tree([6, 4, 2, 1, 3, 5, 7])
# target_tree.display()
assert target_tree.root.parent == None, \
'tree.parent should have been None.'
assert tree.root.parent == None, 'tree.parent should have been None.'
assert bst.size(tree.root) == 7, 'tree size should be 7.'
assert bst.is_valid_tree(tree.root), \
'Valid tree was marked as invalid.'
bst.rotate_left(tree, tree.root)
assert bst.size(tree.root) == 7, 'tree size should be 7.'
assert bst.is_valid_tree(tree.root), \
'Valid tree was marked as invalid.'
assert tree.root.parent == None, 'tree.parent should have been None.'
# This calls tree.__eq__(target_tree). Cool, huh? You need to write
# the __eq__ method in class BST to do the tree comparison.
assert tree == target_tree, '__eq__ did not work properly.'
# This calls tree.__ne__(target_tree).
assert not (tree != target_tree), '__ne__ did not work properly.'
def draw(pic, root, d, side, curr):
'''Draw on Picture pic a picture of the tree rooted at BTNode root, which
appears at depth d in a tree. 'side' is the coordinate that marks the left
of the tree being drawn, and curr is the currently selected value. Most
values appear in black; only the value in curr appears in red.'''
if root != None:
left_size = bst.size(root.left)
# the coordinate where the root will be drawn; the root has
# left_size nodes to the left of it.
x = side + left_size * NODE_WIDTH
# The y coordinate of the root value.
y = d * NODE_HEIGHT
if curr == root:
color = media.red
else:
color = media.black
# Draw the current node's value.
media.add_text(pic, WIDTH_OFFSET + x, HEIGHT_OFFSET + y, \
str(root.data), color)
if root.left:
draw(pic, root.left, d + 1, side, curr)
if root.right:
draw(pic, root.right, d + 1, x + NODE_WIDTH, curr)
def size(self):
"""Returns the number of items in the map
Calls size function in bst.py
Returns:
int: The number of nodes in the TreeMap.
"""
return size(self.tree)
def test_insert_2_left():
'''Test inserting two nodes into a BST where the second value is inserted
into the left of the root; also test size and is_valid_tree.'''
tree = build_tree([5, 3])
assert tree.root.data == 5, 'tree.data not correct for tree of size 2.'
assert tree.root.parent == None, 'tree.parent should have been None.'
assert tree.root.right == None, 'tree.right should have been None.'
assert tree.root.left.data == 3, 'tree.left should have been 3.'
assert tree.root.left.parent == tree.root, \
"tree.left's parent should be root."
assert bst.size(tree.root) == 2, 'tree size should be 2.'
assert bst.size(tree.root.left) == 1, "tree.left's size should be 1."
assert bst.is_valid_tree(tree.root), 'Valid tree was marked as invalid.'
def test_rotate_subtree_left(self):
'''Test left rotation on the root of a tree.'''
# A full binary search tree.
tree = build_tree([4, 2, 1, 3, 6, 5, 7])
old_tree = build_tree([4, 2, 1, 3, 6, 5, 7])
#tree.display()
#print ""
# The expected result.
target_tree = build_tree([4, 2, 1, 3, 7, 6, 5])
#target_tree.display()
assert tree.root.parent == None, 'tree.parent should have been None.'
assert bst.size(tree.root) == 7, 'tree size should be 7.'
assert bst.is_valid_tree(tree.root), \
'Valid tree was marked as invalid.'
bst.rotate_left(tree, tree.root.right)
assert bst.size(tree.root) == 7, 'tree size should be 7.'
assert bst.is_valid_tree(tree.root), \
'Valid tree was marked as invalid.'
assert tree.root.right.data == old_tree.root.right.right.data, \
'''incorrect rotate, tree's new right substree should start
with 7'''
assert tree.root.data == old_tree.root.data, \
'''incorrect rotate, tree's root should not have changed'''
assert tree.root.right.left.left.data == \
old_tree.root.right.left.data, \
'''incorrect rotate, subtree's leftmost leaf should not have
changed'''
#RL is right.left, and LR is left.right
# This calls tree.__eq__(target_tree). Cool, huh? You need to write
# the __eq__ method in class BST to do the tree comparison.
assert tree == target_tree, '__eq__ did not work properly.'
# This calls tree.__ne__(target_tree).
assert not (tree != target_tree), '__ne__ did not work properly.'
def test_insert_1():
'''Test inserting one node into a BST; also test size and
is_valid_tree.'''
tree = bst.BST()
tree.insert(5)
assert tree.root.data == 5, 'tree.data not correct for tree of size 1.'
assert tree.root.parent == None, 'tree.parent should have been None.'
assert tree.root.left == None, 'tree.left should have been None.'
assert tree.root.right == None, 'tree.right should have been None.'
assert bst.size(tree.root) == 1, 'tree size should be 1.'
assert bst.is_valid_tree(tree.root), 'Valid tree was marked as invalid.'
