# Python program to find the node with minimum value in bst
 
# A binary tree node
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))
 
# This code is contributed by Nikhil Kumar Singh(nickzuck_007)