# todo

class Node:
    def __init__(self, v, l = None, r = None):
        self.v = v
        self.l = l
        self.r = r

class BinaryTree:
    def __init__(self, root = None):
        self.root = root

    def find(self, v): pass

    def parent(self, v): pass

    def insert(self, v): pass

    def delete(self, v): pass

    def btmax(self): pass

    def btmin(self): pass

    def prefix(self): pass

    def infix(self): pass

    def sufix(self): pass