C++ Strings Abstract Data Type

Content

• Write a program that reads in two people's names and ages, and writes them out in alphabetical order by last name.
  • Inputs: Name1, Age1, Name2, Age2.
  • Outputs: Name and Age pairs, ordered by name.
  • Design

              Read Name1, Age1
              Read Name2, Age2
              If Name1 > Name2
                  Swap Name1 and Name2
                  Swap Age1 and Age2
              Output Name1 and Age1
              Output Name2 and Age2
              

• NameAgeTwoV5.cpp - The NameAge program, version 5

• The string library for the NameAge program
  • mystrlib.h - My string library header, version 1
  • mystrlib.cpp - My string library implementation, version 1

• Another version of a string library
  • strlib.h - Header file (p.281)
  • strlib.cpp - Implementation file (p.282)
  • testlib.cpp - Using the library (p.283)

• The string Abstract Data Type (ADT) (p.262)
  • An Abstract Data Type (ADT) consists of a set of values, a defined set of properties of these values, and a set of operations for processing the values.
  • The string ADT values are all sequences of characters upto a specified length.
  • Properties
    • The component characters are from the ASCII character set
    • They are comparable in lexicographic order
    • They have a length, from 0 to the specified length
  • Operations on the string ADT include (p.264)
    • Input
    • Output
    • Initialization and assignment
    • Comparison greater, equal, less
    • Determination of length
    • Concatenation
    • Accessing component characters and substrings

• Array of integers example

  Write a program that stores the integer marks of a student for several items of assessment, each of equal value. The program outputs the total and average mark.

  • Marks.cpp - Marks program, version 1 (Monolithic)
  • An integer array library for the Marks program
    • intarraylib.h - Integer array library header, version 1
    • intarraylib.cpp - Integer array library implementation, version 1
  • MarksLib.cpp - Marks program, version 2 (Library)
  • Integer array ADT
    • Set of values: vectors, of a maximal size, of integers
    • Properties: Integers are limited to a maximal size, components are indexed from 0.
    • Operations: Total, Average, Accessing components
  • Problems with this solution
    • User has to use (unfriendly) 0 ... indexing of arrays
    • Number of items is the user's responsibility
    • Marks can be directly changed
  • A better ADT
    • Set of values: vectors, of a maximal size, of integers
    • Properties: Integers are limited to a maximal size, components are indexed from 1, number of values stored is known.
    • Operations: Add a value, Retrieve number of values stored, Retrieve a specified value, Change a specified value, Total, Average
  • MarksStruct.cpp - Marks program with structs (Monolithic)
  • Smart library solution (tutorial work)

• The string ADT

• Building a library

Exam style questions

1. Define an Abstract Data Type (ADT).
2. Describe what is typically found in the header and the implementation files of a library for an Abstract Data Type.