Python program to count the number of nodes in Binary Search Tree.
Description:
This program is to count the number of nodes in Binary Search Tree.
Algo: -
Program:1. Make a class for node in a tree.2. Form the tree by creating nodes.3. Traverse the tree.4. During traversal count the nodes one by one.5. Display the no. of nodes.
#A class that represents the individual node of the Binary tree
class Node:
def __init__(self, key):
self.left = None
self.right = None
self.val = key
#A function to count no. of nodes.
def counter(root,count):
if root:
#First recur the left child
if root.left:
count=counter(root.left,count)
count+=1
#Recur the right child at last
if root.right:
count=counter(root.right,count)
return count
def main():
root = Node(1)
root.left = Node(2)
root.right = Node(3)
root.left.left = Node(4)
root.left.right = Node(5)
root.left.right.left = Node(6)
root.left.right.right = Node(7)
count=0
count=counter(root,count)
print('The no. of nodes in the tree are = ',count)
#Driver code
if __name__ == "__main__":
main()
The no. of nodes in the tree are = 7
