Programming in C

78 Chapter 6 Making Decisions

if ( number < 0 )

sign = -1;

else if ( number == 0 )

sign = 0;

else // Must be positive

sign = 1;

printf ("Sign = %i\n", sign);

return 0;

}

Program 6.6 Output

Please type in a number: 1121

Sign = 1

Program 6.6 Output (Rerun)

Please type in a number: -158

Sign = -1

Program 6.6 Output (Second Rerun)

Please type in a number: 0

Sign = 0

If the number that is entered is less than zero,signis assigned the value –1; if the num-

ber is equal to zero,signis assigned the value 0 ; otherwise, the number must be greater

than zero, so signis assigned the value 1.

Program 6.7 analyzes a character that is typed in from the terminal and classifies it as

either an alphabetic character (a–zor A–Z), a digit (0–9), or a special character (any-

thing else).To read a single character from the terminal, the format characters %care

used in the scanfcall.

Program 6.7 Categorizing a Single Character Entered at the Terminal

// Program to categorize a single character that is entered at the terminal

#include <stdio.h>

int main (void)

{

char c;

Program 6.6 Continued