Chapter 9, Problem 9.4E

Write a printf or scanf statement for each of the following:

1. Print unsigned integer 40000 left justified in a 15-digit field with 8 digits.
2. Read a hexadecimal value into variable hex.
3. Print 200 with and without a sign.
4. Print 100 in hexadecimal form preceded by 0x.
5. Read characters into array s until the letter p is encountered.
6. Print 1.234 in a 9-digit field with preceding zeros.
7. Read a time of the form hh:mm:ss, storing the parts of the time in the integer variables hour, minute and second. Skip the colons (:) in the input stream. Use the assignment suppression character.
8. Read a string of the form “characters” from the standard input. Store the string in character array s. Eliminate the quotation marks from the input stream.
9. Read a time of the form hh:mm:ss, storing the parts of the time in the integer variables hour, minute and second. Skip the colons (:) in the input stream. Do not use the assignment suppression character.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Print unsigned integer 40000 left justified in a 15-digit field with 8 digits.

Explanation:

Following is the print statement to print an unsigned integer 40000 left justified in a 15-digit field with 8 digits:

printf ( “%-15.8u”,40000 ) ;

The printf displays the given number as 8 digits with left justification in a l5 digit field.

• -15 placed to the immediate right of % sign, is used to left justify the number and occupy 15 spaces.
• Digit 8 after the decimal point places zeros to the left of the number to make it an 8-digit number.
• Conversion specifier u is used to print unsigned numbers.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Read a hexadecimal value into variable hex.

Explanation:

Following is the scanf statement to read a hexadecimal value into hex variable:

scanf ( “%x”, hex ) ;

The scanf statement inputs a hexadecimal number in the variable named hex using conversion specifier %x.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Print 200 with and without a sign.

Explanation:

Following is the printf statement to print 200 with and without a sign:

printf ( “%+d\n %d\n”, 200, 200 ) ;

The printf statement prints the value 200, with and without a plus sign. If we place a + sign immediate to the right of %sign, then, a positive value is printed with a plus sign and a negative value is printed with a minus sign.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Print 100 in hexadecimal form preceded by 0x.

Explanation:

Following is the printf statement to print 100 in hexadecimal form preceded by 0x:

printf ( “%#x\n”, 100 ) ;

The printf statement is used to print 100 preceded by Ox. This is accomplished by using a # flag placed immediate to the right of % sign in the field.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Read characters into arrays s until the letter p is encountered.

Explanation:

Following is the scanf statement to read characters into arrays s until the letter p is encountered:

scanf ( “%[^p]”, s ) ;

The scanf statement is used to read the string until the letter p appears. This is achieved by inverted scan set, that is, by placing a Caret (^) before the character.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Print 1.234 in a 9-digit field with preceding zeros.

Explanation:

Following is the printf statement to print 1.234 in a 9-digit field with preceding zeros:

printf ( “%09.3f\n”, 1.234 ) ;

The printf statement prints the given floating-point number in the field of 9 digits and preceded by zeros. Thus achieved by placing 09 immediate to the right of % sign.

Digit 3 after the decimal point is used to provide precision up to 3 values.

Program Plan Intro

To write a printf or scanf statement for the given condition.

Explanation of Solution

Given information:

Write time of the hh: mm: ss type, storing the timepieces in the hour, minute and second integer variables. Skip the colons (:) through the input tube. Use the character assignment Suppression.

Explanation:

Following is the scanf statement to read the time in form hh:mm:ss -:

scanf ( “%d*c%d*c%d”, &hour, &minute, &second ) ;

The scanf statement is used to input the time in the form hh:mm:ss. The colons (:) are eliminated using the suppression character (*) in the field.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Read a string from the standard input of the "characters" type. Place the string in character array s. Eliminate quotation marks from the input stream.

Explanation:

Following is the scanf statement to read a string of characters and store in array s -:

scanf ( “\”%[^\“]”, s ) ;

The scanf statement is used to input a string by the in quotation marks in a character array, s, and eliminate those quotation marks.

This is achieved by using an inverted scan set where a caret (^) before the \” sign is placed.

Program Plan Intro

To write a printf or scanf statement for given condition.

Explanation of Solution

Given information:

Read a time of type hh: mm: ss, storing time pieces in the hour, minute and second integer variables. Skip the input stream colons (:). Do not use the character Assignment Suppression.

Explanation:

Following is the scanf statement to read the time in form hh:mm:ss and skip the colons without using assignment suppression character -:

scanf ( “%d:%d:%d: ”, &hour, &minute, &second ) ;

The scanf statement is used to input the time in the form hh:mm:ss. The colons (:) are eliminated by placing colons (:) in the scanf statement as shown, if we do not have to put suppression character.