Introduction

Abstract

The singly-linked-list data structure provided in Part 1 offers great versatility in what can be programmed, but that versatility has a drawback: there is little to prevent the programmer from creating application code that exhibits certain insidious errors, such as unintentional circularities in lists that cause programs to loop indefinitely. But we can build upon the singly-linked-list structure and restrict the kinds of operations upon it, using data abstraction, providing security against some kinds of errors. Thus, aside from potentially providing greater efficiency in the situations in which they can be used, the three linear data structures provided in this part may be a better choice than direct use of singly-linked lists, especially for less experienced programmers.