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5-3 Multiway Selection

In addition to two-way selection, most programming In addition to two-way selection, most programming languages provide another selection concept known as languages provide another selection concept known as multiway selection. Multiway selection chooses among multiway selection. Multiway selection chooses among several alternatives. C has two different ways to several alternatives. C has two different ways to implement multiway selection: the implement multiway selection: the switchswitch statement statement and and else-ifelse-if construct. construct.

The switch StatementThe else-if

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FIGURE 5-19 switch Decision Logic

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FIGURE 5-20 switch Statement Syntax

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FIGURE 5-21 switch Flow

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PROGRAM 5-6 Demonstrate the switch Statement

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FIGURE 5-22 switch Results

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FIGURE 5-23 A switch with break Statements

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PROGRAM 5-7 Multivalued case Statements

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Table 5-5 Summary of switch Statement Rules

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PROGRAM 5-8 Student Grading

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PROGRAM 5-8 Student Grading

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PROGRAM 5-8 Student Grading

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FIGURE 5-24 The else-if Logic Design for Program 5-9

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The else-if is an artificial C construct that is only used when1. The selection variable is not an integral, and2. The same variable is being tested in the expressions.

NoteNote

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PROGRAM 5-9 Convert Score to Grade

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PROGRAM 5-9 Convert Score to Grade

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PROGRAM 5-9 Convert Score to Grade

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5-4 More Standard Functions

One of the assets of the C language is its rich set of One of the assets of the C language is its rich set of standard functions that make programming much standard functions that make programming much easier. For example, C99 has two parallel but separate easier. For example, C99 has two parallel but separate header files for manipulating characters: ctype.h and header files for manipulating characters: ctype.h and wctype.h.wctype.h.

Standard Characters FunctionsA Classification ProgramHandling Major Errors

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FIGURE 5-25 Classifications of the Character Type

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Table 5-6 Classifying Functions

continued

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Table 5-6 Classifying Functions (continued)

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Table 5-7 Conversion Functions

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PROGRAM 5-10 Demonstrate Classification Functions

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PROGRAM 5-10 Demonstrate Classification Functions