class Wezel:
    def __init__(self, key):
        self.key = key
        self.left = None
        self.right = None


class Drzewo:
    def __init__(self):
        self.me = None

    def insert(self, key):
        if ( self.me == None ):
            self.me = Wezel(key)
        else:
            done = False
            target = self.me
            while done != True:
                if (target.left == None and key < target.key):
                    target.left = Wezel(key)
                    done = True
                elif (target.left != None and key < target.key):
                    target = target.left
                if (target.right == None and key > target.key):
                    target.right = Wezel(key)
                    done = True
                elif (target.right != None and key > target.key):
                    target = target.right

    def find(self, key):
        done = False
        target = self.me
        while done != True:
            if (key == target.key):
                return target
                done = True
            elif (key > target.key and target.right != None):
                temp = target.right
                target = temp
            elif (key < target.key and target.left != None):
                temp = target.left
                target = target.left

    def tree_walk(self):
        def tree_walk(wezel):
            if (wezel != None):
                tree_walk(wezel.left)
                print(wezel.key)
                tree_walk(wezel.right)

        tree_walk(self.me)



asd = Drzewo()

asd.insert(5)
asd.insert(3)
asd.insert(8)
asd.insert(2)
asd.insert(6)
asd.insert(4)
asd.insert(9)
asd.insert(1)
asd.insert(7)

buff = asd.find(2)

asd.tree_walk()
print("DONE")