When it is required to sort a binary search tree, a class is created, and methods are defined inside it that perform operations like inserting an element, and performing inorder traversal.
Below is a demonstration of the same −
Example
class BinSearchTreeNode:
def __init__(self, key):
self.key = key
self.left = None
self.right = None
self.parent = None
def insert_elem(self, node):
if self.key > node.key:
if self.left is None:
self.left = node
node.parent = self
else:
self.left.insert_elem(node)
elif self.key <= node.key:
if self.right is None:
self.right = node
node.parent = self
else:
self.right.insert_elem(node)
def inorder_traversal(self):
if self.left is not None:
self.left.inorder_traversal()
print(self.key, end=' ')
if self.right is not None:
self.right.inorder_traversal()
class BinSearchTree:
def __init__(self):
self.root = None
def inorder_traversal(self):
if self.root is not None:
self.root.inorder_traversal()
def add_val(self, key):
new_node = BinSearchTreeNode(key)
if self.root is None:
self.root = new_node
else:
self.root.insert_elem(new_node)
my_instance = BinSearchTree()
my_list = input('Enter the list of numbers... ').split()
my_list = [int(x) for x in my_list]
for x in my_list:
my_instance.add_val(x)
print('Sorted list: ')
print(my_instance.inorder_traversal())Output
Enter the list of numbers... 67 54 89 0 11 34 99 Sorted list: 0 11 34 54 67 89 99
Explanation
The ‘BinSearchTreeNode’ class with required attributes is created.
It has an ‘init’ function that is used to assign ‘left’, ‘right’ and ‘parent’ nodes to ‘None’.
Another method named ‘insert_elem’ is defined that helps add nodes to the tree.
Another method named ‘inorder_traversal’ is defined, that helps perform inorder traversal on the tree.
Another class named ‘BinSearchTree’ is defined.
It sets the root to ‘None.
It has a method named ‘inorder_traversal’ that helps perform inorder traversal on the tree.
Another method named ‘add_val’ is defined that helps add nodes to the tree.
An instance of the ‘BinSearchTree’ is created.
The list of numbers is taken by user.
A tree is created using this.
The list is sorted, and its inorder traversal is performed.
Relevant output is displayed on the console.