BST in Python
class BSTNode:
def __init__(self, val=None):
self.left = None
self.right = None
self.val = val
def insert(self, val):
if not self.val:
self.val = val
return
if self.val == val:
return
if val < self.val:
if self.left:
self.left.insert(val)
return
self.left = BSTNode(val)
return
if self.right:
self.right.insert(val)
return
self.right = BSTNode(val)
def get_min(self):
current = self
while current.left is not None:
current = current.left
return current.val
def get_max(self):
current = self
while current.right is not None:
current = current.right
return current.val
def delete(self, val):
if self == None:
return self
if val < self.val:
if self.left:
self.left = self.left.delete(val)
return self
if val > self.val:
if self.right:
self.right = self.right.delete(val)
return self
if self.right == None:
return self.left
if self.left == None:
return self.right
min_larger_node = self.right
while min_larger_node.left:
min_larger_node = min_larger_node.left
self.val = min_larger_node.val
self.right = self.right.delete(min_larger_node.val)
return self
def exists(self, val):
if val == self.val:
return True
if val < self.val:
if self.left == None:
return False
return self.left.exists(val)
if self.right == None:
return False
return self.right.exists(val)
def preorder(self, vals):
if self.val is not None:
vals.append(self.val)
if self.left is not None:
self.left.preorder(vals)
if self.right is not None:
self.right.preorder(vals)
return vals
def inorder(self, vals):
if self.left is not None:
self.left.inorder(vals)
if self.val is not None:
vals.append(self.val)
if self.right is not None:
self.right.inorder(vals)
return vals
def postorder(self, vals):
if self.left is not None:
self.left.postorder(vals)
if self.right is not None:
self.right.postorder(vals)
if self.val is not None:
vals.append(self.val)
return vals
Worrisome Worm