I am reading about algorithms and got to the binary search trees. I wanted to ask if the following implementation of a Binary Tree is correct.
import random
class Tree(object):
def __init__(self):
self.root = Node()
def insert(self,data):
self.root.insert(data)
def delete(self,data):
self.root.delete(data)
def print_elements(self):
return self.root.print_element()
class Node(object):
def __init__(self,data = None, parent = None):
self.parent = parent
self.data = data
self.left = None
self.right = None
def insert(self,data):
if self.data == None:
self.data = data
else:
if data < self.data:
if self.left == None:
self.left = Node(data,self)
else:
self.left.insert(data)
else:
if data > self.data:
if self.right == None:
self.right = Node(data,self)
else:
self.right.insert(data)
def delete(self,data):
if self.data == data:
if self.right == None and self.left == None:
if self.parent.left.data == data:
self.parent.left = None
else:
self.parent.right = None
elif self.right == None or self.left == None:
if self.right == None:
self.data , self.left = self.left.data , self.left.left
else:
self.data, self.right = self.right.data , self.right.right
else:
counter = self.right
while True:
if counter.right == None:
break
else:
counter = counter.left
self.data = counter.data
counter.delete(counter.data)
else:
if data < self.data:
self.left.delete(data)
else:
self.right.delete(data)
def search(self,data):
if self.data == data:
return self.data
else:
if data < self.data:
return self.left.search(data)
else:
return self.right.search(data)
def print_element(self):
if self.parent:
print self.data, 'is below %s' % (self.parent.data)
else:
print self.data
if self.right != None:
self.right.print_element()
if self.left != None:
self.left.print_element()
The other thing I want to ask is, when I am implementing these data structures (also happened with linked lists) I find it easier to implement the methods in the Node class and not in the BT/LL class. Is this normal with Python ? I mean, I see the guides with C++ and the methods are mostly implemented in the BT/LL classes , but they use pointers and pointers are not available in Python. Am I doing it wrong ?
t = Tree(); t.insert(1); t.insert(1)result intcontaining only one node. Why? – Mathias Ettinger Dec 3 '16 at 11:43