A New Algorithm for Minimum Cost Binary Trees

Abstract

A new algorithm for constructing minimum cost binary trees in $O(n \log n)$ time is presented. The algorithm is similar to the well-known Hu-Tucker algorithm. Our proof of validity is based on finite variational methods and is therefore quite different and somewhat simpler than the proof for the Hu-Tucker algorithm. Our proof also yields some additional information about the structure of minimum cost binary trees. This permits a linear time implementation of our algorithm in a special case.