Java Collections_ An Introduction to Abstract D..

566 Pages·2008·15.45 MB·English

Java Collections
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Java Collections
An Introduction to Abstract
Data Types, Data Structures
and Algorithms
David A. Watt
University of Glasgow
Deryck F. Brown
The Robert Gordon University
JOHN WILEY & SONS, LTD
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A catalogue record for this book is available from the British Library
ISBN 0471 89978 X
Cover Image — Fondaco dei Turchi, Venice (w/c) by John Ruskin (1819–1900)
Ruskin Museum, Coniston, Cumbria, UK/Bridgeman Art Library
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Contents
Preface xi
1 Introduction i
I. I Historical background I
1.2 Algorithms and programs 6
1.3 Abstract data types and data structures 7
Summary 9
Exercises 9
2 Algorithms 11
2.1 Principles of algorithms 1 I
2.2 Efficiency of algorithms ) 4
2.3 Complexity of algorithms i 7
2.4 Recursive algorithms 24
Summary 31
Exercises 3 i
3 The Array Data Structure 34
3.1 Arrays 34
3.2 Insertion 38
3.3 Deletion 39
3.4 Searching 40
3.5 Merging 46
3.6 Sorting 49
Summary 62
Exercises 62
4 Linked-List Data Structures 67
4.1 Linked lists 67
4.2 Insertion 78
vi Contents
4.3 Deletion 81
4.4 Searching 86
4.5 Merging 88
4.6 Sorting 91
Summary 94
Exercises 95
5 Abstract Data Types 97
5.1 Datatypes 97
5.2 Abstract data types 103
5.3 Abstract data type design 111
5.4 String abstract data types 114
5.5 Collection abstract data types 120
5.6 Abstract data types in the Java class library 120
Summary 122
Exercises 123
6 Stack Abstract Data Types 125
6.1 The concept of a stack 125
6.2 Applications of stacks 125
6.3 A stack abstract data type 129
6.4 Implementation of bounded stacks using arrays I 30
6.5 Implementation of unbounded stacks using linked lists 132
6.6 Case study: solving and generating mazes 135
Summary 146
Exercises 146
7 Queue Abstract Data Types 149
7.1 The concept of a queue 149
7.2 Applications of queues 149
7.3 A queue abstract data type 151
7.4 Implementation of bounded queues using arrays 152
7.5 Implementation of unbounded queues using linked lists 156
7.6 Case study: a traffic simulator 157
Summary 166
Exercises 167
8 List Abstract Data Types 170
8.1 The concept of a list 170
8.2 Applications of lists 171
8.3 A list abstract data type 172
8.4 Iterators 175
8.5 Implementation of bounded lists using arrays 179
8.6 Implementation of unbounded lists using linked lists 185
8.7 Lists in the Java class library 191
8.8 Case study: a videotape manager
Summary
Exercises
9 Set Abstract Data Types
9.1 The concept of a set
9.2 Applications of sets
9.3 A set abstract data type
9.4 Implementation of bounded sets using arrays
9.5 Implementation of unbounded sets using linked lists
9.6 Implementation of small-integer sets using boolean arrays
9.7 Sets in the Java class library
9.8 Case study: an interactive spell-checker
Summary
Exercises
10 Binary Tree Data Structures 236
10.1 Binary trees 236
10.2 Searching 242
10.3 Insertion 245
10.4 Deletion 247
10.5 Traversal 256
10.6 Merging 26!
10.7 Implementation of unbounded sets using binary search trees 262
Summary 270
Exercises 270
11 Map Abstract Data Types 274
11.1 The concept of a map 274
11.2 Applications of maps 276
I11.3 A map abstract data type 277
I 1.4 Implementation of small-integer-key maps using key-indexed arrays 281
11.5 Implementation of bounded maps using arrays 283
11.6 Implementation of unbounded maps using linked lists 287
11.7 Implementation of unbounded maps using binary search trees 288
11.8 Maps in the Java class library 290
11.9 Case study: a student record system 293
Summary 303
Exercises 304
12 Hash-Table Data Structures 307
12.1 Hash tables 307
12.2 Closed-bucket hash tables 309
12.3 Open-bucket hash tables 316
12.4 Implementations of sets using hash tables 331
viii Contents
12.5 Implementations of maps using hash tables 332
Summary 334
Exercises 334
13 Priority-Queue Abstract Data Types 337
I 3.1 The concept of a priority queue 337
13.2 Applications of priority queues 338
13.3 A priority-queue abstract data type 339
13.4 Implementations of priority queues using linked lists 341
13.5 The heap data structure 344
13.6 Implementation of priority queues using heaps 355
I 3.7 Case study: an improved traffic simulator 355
Summary 361
Exercises 363
14 Tree Abstract Data Types 366
14.1 The concept of a tree 366
14.2 Applications of trees 367
14.3 A tree abstract data type 369
14.4 A linked implementation of trees 369
14.5 Specialized tree abstract data types 378
14.6 Case study: game playing 381
Summary 394
Exercises 395
15 Graph Abstract Data Types 397
15.1 The concept of a graph 397
15.2 Applications of graphs 399
15.3 Graph abstract data types 400
15.4 Edge-set representation of graphs 403
15.5 Adjacency-set representation of graphs 408
15.6 Adjacency-matnx representation of graphs 413
15.7 Graph traversal 415
15.8 Topological sort 420
15.9 Case study: material requirements planning 422
Summary 431
Exercises 431
16 Balanced Search Tree Data Structures 435
16.1 AVL-trees 435
16.2 B-trees 447
Summary 466
Exercises 467
17 Conclusion 469
17.1 Abstract data types and object-oriented design 469
17.2 Abstract data types as reusable software components 47!
17.3 Homogeneous and heterogeneous collections 472
i 7.4 Extending Java with parameterized classes 476
17.5 Case study: a student record system revisited 477
Summary 482
Exercises 482
A Summary of Mathematics for Algorithm Analysis 484
A.I Powers 484
A.2 Logarithms 486
A3 Series summations 487
A,4 Recurrences 488
A.5 O-notation 490
B Summary of Java 495
B.I Basics 495
B.2 Classes
B.3 Interfaces
B.4 Packages
B.5 Exceptions
B.6 Inner classes and inner interfaces
C Summary of the Java Collections Framework 5) 7
C.I Collections 517
C.2 Lists 520
C.3 Sets 524
C.4 Maps 528
C.5 Orderings 533
C.6 Iterators 534
Further reading 537
Bibliographic notes 537
Bibliography 539
Index 540