Write a Python program that takes a list of integers as input and returns the two numbers in the list that add up to a given target value. If no such pair exists, return an empty list. Your program should be able to handle large input lists efficiently.

Question 2: Implement a Python function that uses dynamic programming to efficiently compute the n-th Fibonacci number. Your function should take an integer n as input and return the corresponding Fibonacci number

Question 3: Write a Python class that implements a binary search tree. The class should support the following operations: insert, delete, search, and traversal (in-order, pre-order, and post-order). Your class should also be able to handle duplicate values.