Roselyn Teukolsky - Barrons AP Computer Science A

About the Author:

Roselyn Teukolsky has an M.S. dedgree from Cornell University, and has been teaching programming and computer science since 1980. She has published articles in The Mathematics Teacher and in the National Council of Teachers of Mathematics Yearbook. She is the author of Barrons ACT Math and Science Workbook and co-author of Barrons SAT 1600: Aiming for the Perfect Score. She has received the Edyth May Sliffe Award for Distinguished Mathematics Teaching and the Alfred Kalfus Distinguished Coach Award from the New York State Math League (NYSML).

Copyright 2020, 2018, 2015, 2013, 2010 by Kaplan, Inc.,

d/b/a Barrons Educational Series

Previous editions copyright 2007 under the title

AP Computer Science Levels A and AB, 2003 under the title

How to Prepare for the AP Computer Science Advanced Placement Examination, JAVA Version, and 2001 under the title How to Prepare for the AP Computer Science Advanced Placement Examination

by Kaplan, Inc., d/b/a Barrons Educational Series

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d/b/a Barrons Educational Series

750 Third Avenue

New York, NY 10017

www.barronseduc.com

ISBN: 978-1-5062-7200-9

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Barrons Essential

As you review the content in this book to work toward earning that on your AP Computer Science A exam, here are five things that you MUST know above everything else:

The Basics. Every AP exam question uses at least one of these:

Types and identifiers ()

Operators ()

Control structures ()

Objects, Classes, and Inheritance. You may have to write your own class. Youll definitely need to interpret at least one class thats given.

Methods ()

Superclasses ()

Subclasses ()

Lists and Arrays. Learn to manipulate a list. Search, delete an item, insert an item. It seems as if every second question on the AP exam uses a list!

One-dimensional arrays ()

ArrayLists ()

Two-Dimensional Arrays. Learn tomanipulate amatrix. This topic has become more prominent on the AP exam in recent years.

Two-dimensional arrays ()

Row-column traversal ()

For-each loop traversal ()

Row-by-row array processing ()

Sorting and Searching. Know these algorithms!

Selection sort ()

Insertion sort ()

Merge sort ()

Sequential search ()

Binary search ()

This book is aimed at students reviewing for the AP Computer Science A exam. It would normally be used at the completion of an AP course. However, it contains a complete summary of all topics for the exam, and it can be used for self-study if accompanied by a suitable textbook.

The book provides a review of object-oriented programming, algorithm analysis, and data structures. It can therefore be used as a supplement to a first-semester college course where Java is the programming language, and as a resource for teachers of high school and introductory college courses.

New to this ninth edition are

Updated practice tests that conform to the requirements of the Fall 2019 Course and Exam Description for AP Computer Science A.

Many new multiple-choice and free-response questions.

Many streamlined free-response questions that closely follow the style and numbering conventions of recent and future AP exams.

An updated section on analyzing the binary search algorithm.

Updated scoring rubrics for the free-response questions.

This edition covers all features of Java that will be tested on the AP exam, including topics that are emphasized on the exam: arrays, two-dimensional arrays, strings, list-processing, and inheritance in object-oriented programming. There are multiple questions on enhanced for loops (using a for-each loop traversal), and treating a matrix as an array of arrays. Additionally, theres a chapter that covers the AP Computer Science A labs that were developed to satisfy the lab requirement for AP Computer Science A. There are no questions on the AP exam that test the specific content of the labs, but there are questions that test the concepts developed in the labs. is exclusively devoted to these concepts.

Changes that go into effect for the May 2020 exam are marked with a lightning" symbol in the margin, as shown here.

Note that the ninth edition has been updated to reflect the facts that abstract classes, interfaces, List, and number systems other than base 10 are no longer part of the AP Java subset, but autoboxing and ConcurrentModificationException are new to the subset.

The style of all questions and examples in the book continues to reflect the style of recent exams.

There are six complete practice tests. The practice tests follow the format of the AP exam, with multiple-choice and free-response sections. One practice test is presented after the introduction to the book for possible use as a diagnostic test. A diagnostic chart accompanies this test. There are two practice tests at the end of the book. Detailed solutions with explanations and scoring rubrics are provided for all tests. There is no overlap of questions between the practice tests.

Note that the scoring worksheets that accompany each test have been updated to reflect the College Board policy of not penalizing students for wrong answers on the multiple-choice section.

Many people helped in the creation of this book.

I would like to thank my editor, Annie Bernberg, for her kindness, expertise, and assurance in taking the reins of the project. Thanks also to Christine Ricketts, production editor, and Mary Behr, copyeditor, as well as Jeff Batzli, Alison Maresca, Jalisa Valladares, Mandy Luk, and all the other members of the Kaplan staff who worked on the production of the book and online tests.

I am most grateful to my former editor, Linda Turner, of Barrons, for her friendly guidance and moral support over many years.

A very special thank you to Judy Hromcik and Richard Kick who went above and beyond in checking content and making valuable suggestions.

Thank you to all of the computer science teachers throughout the country who took time to write to me with suggestions.

My husband, Saul, continues to be my partner in this projecttypesetting the manuscript, producing the figures, and giving advice and moral support. This book is dedicated to him.

Roselyn Teukolsky
Ithaca, NY
September 2019

Computer Science: The boring art of coping with a large number of trivialities.
Stan Kelly-Bootle,