How to make huffman tree in scheme?

Question

I am trying to make huffman encoding/decoding in scheme so i have function "frequencies" which makes frequencies list. I made also function which found the the pair form the list with the smallest frequencies and a function which remove the pair with the smallest frequencies from the list. And i dont understand how to make the tree. And when i have the tree how to start encoding? I also have funct.which combine the two pairs with the smallest frequencies into one pair like this (a.3) (b.5) ->((ab).8)

Answer 1

You'll discover a very detailed explanation of Huffman Encoding Trees in section 2.3.4 of the classic book SICP , available online. There you'll find a description of the inner workings of such a tree, along with a complete implementation. You'll only need to adapt it to the interfaces/data structures provided for your assignment.