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Addison Wesley is an imprint of

Chapter 11:Structure and Union Types

Problem Solving & Program Design in C

Sixth Edition

By Jeri R. Hanly &

Elliot B. Koffman

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Structures and Union Types

A database is a collection of information stored in a computer’s memory or in a disk file.

A database is subdivided into records, which normally contains information regarding specific data objects.

The structure of the record is determined by the structure of the object’s data type.

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Structures and Union TypesDefine a structure type before it can be created or saved. #define STRSZ 10typedef struct {

char name[STRSZ];double diameter;int moons;double orbit_time, rotation_time;

} planet_t

planet_t current_planet, previous_planet, blank_planet = { “”, 0, 0, 0, 0};

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Figure 11.1 Assigning Values to Components of Variable current_planet p569

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Figure 11.2 Function with a Structured Input Parameter

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Figure 11.3 Function Comparing Two Structured Values for Equality

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Figure 11.3 Function Comparing Two Structured Values for Equality (cont’d)

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Figure 11.4 Function with a Structured Output Argument

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Figure 11.5 Data Areas of main and scan_planet during Execution of status = scan_planet (&current_planet);

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Figure 11.6 Function get_planet Returning a Structured Result Type

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Figure 11.7 Function to Compute an Updated Time Value

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Figure 11.8 Structured Values as a Function Input Argument and as a Function Result

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Figure 11.9 Data Type planet_t and Basic Operations

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Figure 11.10 Partial Implementation of Type and Operators for Complex Numbers

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Figure 11.10 Partial Implementation of Type and Operators for Complex Numbers (cont’d)

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Figure 11.10 Partial Implementation of Type and Operators for Complex Numbers (cont’d)

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Figure 11.10 Partial Implementation of Type and Operators for Complex Numbers (cont’d)

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Figure 11.10 Partial Implementation of Type and Operators for Complex Numbers (cont’d)

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Figure 11.11 An Array of Structures

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Figure 11.12 Universal Measurement Conversion Program Using an Array of Structures

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Figure 11.12 Universal Measurement Conversion Program Using an Array of Structures (cont’d)

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Figure 11.12 Universal Measurement Conversion Program Using an Array of Structures (cont’d)

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Figure 11.12 Universal Measurement Conversion Program Using an Array of Structures (cont’d)

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Figure 11.12 Universal Measurement Conversion Program Using an Array of Structures (cont’d)

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Figure 11.13 Data File and Sample Run of Measurement Conversion Program

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Figure 11.14 Function That Displays a Structure with a Union Type Component

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Figure 11.15 Two Interpretations of Parameter hair

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Figure 11.16 Program to Compute Area and Perimeter of Geometric Figures

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Figure 11.16 Program to Compute Area and Perimeter of Geometric Figures (cont’d)

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Figure 11.16 Program to Compute Area and Perimeter of Geometric Figures (cont’d)

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Figure 11.16 Program to Compute Area and Perimeter of Geometric Figures (cont’d)