2 : Efficient Binary Search Tree (10%) Program the search, insert, and delete operations for red-black trees. 1. search x : Print out the color of the tree node if the element x exists. If the element x does not exist, print out Not found . 2. insert x : Add an integer x to the red-black tree. If x already exists, do nothing. 3. delete x : Delete the element x if the element x exists. (Note: The textbook did not describe how to implement delete on red-black tree. Students can write your own delete to satisfy the constraint of the red-black tree.) The instructions are insert, search, delete and quit. Instruction quit means you should terminate your program