return root.val
else:
# Leaf Node
# smaller and has value
# case 1
parent = root.parent
while parent and parent.val < root.val:
parent = parent.parent
else:
# TOREAD
# parent may be None
if parent and parent.val > root.val:
return parent.val
else:
#case 2 last element
return None
elif root.val < target:
root = root.right
else:
root = root.left
return None
if __name__ == '__main__':
tree = build_tree_with_parent([100, 50, 200, 25, 75, 125, 350])
print_tree(tree)
print
print inorder_success_bst_with_parent(tree, 350)
res = find_n_rec(root.right, n)
if res:
return res
global cur_count
cur_count += 1
if n == cur_count:
return root.val
res = find_n_rec(root.left, n)
if res:
return res
return
return find_n_rec(bst, nth)
if __name__ == '__main__':
binary_search_tree = \
build_tree([100, 50, 200, 25, 75, 125, 350])
print_tree(binary_search_tree)
val = find_nth_highest(binary_search_tree, 3)
print
print 'nth highest is: ' + str(val)
assert 125 == val
print better_solve1(binary_search_tree, 3)
print better_solve2(binary_search_tree, 3)
if root1 is None and root2 is None:
return True
# if root1.val == root2.val:
# return dfs(root1.left, root2.left) and \
# dfs(root1.right, root2.right)
# else:
# return False
# TOREAD: better wrote
if root1 is not None and root2 is not None:
return (root1.val == root2.val) and \
dfs(root1.left, root2.left) and \
dfs(root1.right, root2.right)
else:
return False
return dfs(tree1, tree2)
if __name__ == '__main__':
tree1 = tree2 = build_tree([100, 50, 200, '#', 25, 125, 350])
print_tree(tree1)
assert True == check_identical_trees(tree1, tree2)
tree1 = build_tree([100, 50, 200, '#', 25, 125, 350])
tree2 = build_tree([100, 50, 200, '#', 25, 125, 250])
print_tree(tree1)
print_tree(tree2)
assert False == check_identical_trees(tree1, tree2)
from helper import build_tree
from helper import print_tree
def transfer(root):
tree = root
visited = [root]
while len(visited):
root = visited.pop()
if root.left:
root.left.parent = root
visited.append(root.left)
# TOREAD: this is not elif
# be careful, elif only when the first one is not right
if root.right:
root.right.parent = root
visited.append(root.right)
return tree
if __name__ == '__main__':
tree = build_tree([100, 50, 200, 25, 75, 125, 350])
print_tree(tree)
root = transfer(tree)
print_tree(root)