swiftSwift Trees

func inOrderTraversal(_ node: Node<Int>?) {
    guard let node = node else { return }
    inOrderTraversal(node.left)
    print(node.value, terminator: " ")
    inOrderTraversal(node.right)
}

func preOrderTraversal(_ node: Node<Int>?) {
    guard let node = node else { return }
    print(node.value, terminator: " ")
    preOrderTraversal(node.left)
    preOrderTraversal(node.right)
}

func postOrderTraversal(_ node: Node<Int>?) {
    guard let node = node else { return }
    postOrderTraversal(node.left)
    postOrderTraversal(node.right)
    print(node.value, terminator: " ")
}