Inorder, Preorder, Postorder traversals

binarytree.py

class Node:
    def __init__(self, data):
        self.data = data
        self.left = None
        self.right = None

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

    def inorder(self, curr):
        if curr is None:
            return

        self.inorder(curr.left)
        print(curr.data, end = ' ')
        self.inorder(curr.right)

    def preorder(self, curr):
        if curr is None:
            return

        print(curr.data, end = ' ')
        self.preorder(curr.left)
        self.preorder(curr.right)

    def postorder(self, curr):
        if curr is None:
            return

        self.postorder(curr.left)
        self.postorder(curr.right)
        print(curr.data, end = ' ')

tree = BinaryTree()
tree.root = Node(1)
tree.root.left = Node(2)
tree.root.right = Node(3)
tree.root.left.left = Node(4)
tree.root.left.right = Node(5)
tree.root.right.left = Node(6)
tree.root.right.right = Node(7)
print("The inorder traversal is:")
tree.inorder(tree.root)
print()
print("The preorder traversal is:")
tree.preorder(tree.root)
print()
print("The postorder traversal is")
tree.postorder(tree.root)
print()