Minimum element in BST Python

PROGRAM TO FIND THE NODE WITH MINIMUM VALUE IN A BINARY SEARCH TREE




class Node:

  

    # Constructor to create a new node

    def __init__(self, key):

        self.data = key

        self.left = None

        self.right = None

  

""" Give a binary search tree and a number, 

inserts a new node with the given number in 

the correct place in the tree. Returns the new 

root pointer which the caller should then use 

(the standard trick to avoid using reference 

parameters). """

def insert(node, data):

  

    # 1. If the tree is empty, return a new,

    # single node

    if node is None:

        return (Node(data))

  

    else:

        # 2. Otherwise, recur down the tree

        if data <= node.data:

            node.left = insert(node.left, data)

        else:

            node.right = insert(node.right, data)

  

        # Return the (unchanged) node pointer

        return node

  

""" Given a non-empty binary search tree,  

return the minimum data value found in that 

tree. Note that the entire tree does not need 

to be searched. """

def minValue(node):

    current = node

  

    # loop down to find the lefmost leaf

    while(current.left is not None):

        current = current.left

  

    return current.data

  

# Driver program

root = None

root = insert(root,4)

insert(root,2)

insert(root,1)

insert(root,3)

insert(root,6)

insert(root,5)

  

print "\nMinimum value in BST is %d"  %(minValue(root))




OUTPUT:

Minimum value in BST is 1

CREDITS: https://www.geeksforgeeks.org/find-the-minimum-element-in-a-binary-search-tree/