Sams Teach Yourself C in 21 Days

Advanced Program Control 329

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default:

printf( “I don’t have a case for %c”, letter );

}

Example 2

switch( number )

{

case 0: puts( “Your number is 0 or less.”);

case 1: puts( “Your number is 1 or less.”);

case 2: puts( “Your number is 2 or less.”);

case 3: puts( “Your number is 3 or less.”);

case 99: puts( “Your number is 99 or less.”);

break;

default: puts( “Your number is greater than 99.”);

}

Because there are no breakstatements for the first casestatements, this example finds

thecasethat matches the number and prints every casefrom that point down to the

breakincase 99. If the number was 3 , you would be told that your number is equal to 3

or less, 4 or less, 5 or less, up to 99 or less. The program continues printing until it

reaches the breakstatement in case 99.

,

,

DOuse a defaultcase in a switchstate-

ment, even if you think you’ve covered

all possible cases.

DOuse a switchstatement instead of an

ifstatement if more than two condi-

tions are being evaluated for the same

variable.

DOline up your casestatements so that

they’re easy to read.

DON’Tforget to use breakstatements if

yourswitchstatements need them.

DO DON’T

Exiting the Program ............................................................................................

A C program normally terminates when execution reaches the closing brace of the

main()function. However, you can terminate a program at any time by calling the

library function exit(). You can also specify one or more functions to be automatically

executed at termination.

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