SICP Exercise 2.67

2023-02-05

Question

Define an encoding tree and a sample message:

(define sample-tree
  (make-code-tree
   (make-leaf 'A 4)
   (make-code-tree
    (make-leaf 'B 2)
    (make-code-tree
     (make-leaf 'D 1)
     (make-leaf 'C 1)))))

(define sample-message
  '(0 1 1 0 0 1 0 1 0 1 1 1 0))

Use the decode procedure to decode the message, and give the result.

Answer

Just execute the function, we already have everything we need:

(decode sample-message sample-tree)

Result:

(A D A B B C A)