Chapter 10

Question 1

What header file must you include in a program using character testing functions such as
isalpha and isdigit ?

Answer 1

cctype

Question 2

What header file must you include in a program using the character conversion functions
toupper and tolower ?

Answer 2

cctype

Question 3

Assume c is a char variable. What value does c hold after each of the following statements
executes?
Statement Contents of c
c = toupper(‘a’); ___________
c = toupper(‘B’); ___________
c = tolower(‘D’); ___________
c = toupper(‘e’); __________

Answer 3

‘A’
‘B’
‘d’
‘E’

Question 4

Look at the following code. What value will be stored in s after the code executes?
char name[10];
int s;
strcpy(name, “Jimmy”);
s = strlen(name);

Answer 4

5

Question 5

What header file must you include in a program using string functions such as strlen and
strcpy ?

Answer 5

cstring

Question 6

What header file must you include in a program using string/numeric conversion functions
such as atoi and atof ?

Answer 6

cstdlib

Question 7

7. What header file must you include in a program using string class objects?

Answer 7

string

Question 8

8. How do you compare string class objects?

Answer 8

With the standard relational operators.

Question 9

The _________ function returns true if the character argument is uppercase.

Answer 9

isupper

Question 10

10. The _________ function returns true if the character argument is a letter of the alphabet.

Answer 10

isalpha

Question 11

11. The _________ function returns true if the character argument is a digit.

Answer 11

isdigit

Question 12

12. The _________ function returns true if the character argument is a whitespace character.

Answer 12

isspace

Question 13

13. The _________ function returns the uppercase equivalent of its character argument.

Answer 13

toupper

Question 14

14. The _________ function returns the lowercase equivalent of its character argument.

Answer 14

tolower

Question 15

15. The _________ file must be included in a program that uses character testing functions.

Answer 15

cctype

Question 16

16. The _________ function returns the length of a string.

Answer 16

strlen

Question 17

17. To _________ two strings means to append one string to the other.

Answer 17

concatenate

Question 18

18. The _________ function concatenates two strings.

Answer 18

strcat

Question 19

19. The _________ function copies one string to another.

Answer 19

strcpy

Question 20

20. The _________ function searches for a string inside of another one.

Answer 20

strstr

Question 21

21. The _________ function compares two strings.

Answer 21

strcmp

Question 22

22. The _________ function copies, at most, n number of characters from one string to another.

Answer 22

strncpy

Question 23

23. The _________ function returns the value of a string converted to an integer.

Answer 23

atoi

Question 24

24. The _________ function returns the value of a string converted to a long integer.

Answer 24

atol

Question 25

25. The _________ function returns the value of a string converted to a float.

Answer 25

atof

Question 26

26. The _________ function converts an integer to a string.

Answer 26

itoa

Question 27

27. The following if statement determines whether choice is equal to ‘ Y ’ or ‘ y ’.
    if (choice == ‘Y’ || choice == ‘y’)
    Simplify this statement by using either the toupper or tolower function

Answer 27

if (toupper(choice) == ‘Y’)

Question 28

28. Assume input is a char array holding a C-string. Write code that counts the number
    of elements in the array that contain an alphabetic character.

Answer 28

int numAlpha = 0; // Accumulator
int i = 0; // Loop counter
while (input[i] != ‘\0’)
{
if (isalpha(input[i]))
numalpha++;
}

Question 29

29. Look at the following array definition.
    char str[10];
    Assume that name is also a char array, and it holds a C-string. Write code that copies the
    contents of name to str if the C-string in name is not too big to fit in str .

Answer 29

if (strlen(name) <= 9)
strcpy(str, name);

Question 30

30. Look at the following statements.
    char str[] = “237.89”;
    double value;

Write a statement that converts the string in str to a double and stores the result in value .

Answer 30

value = atof(str);

Question 31

31. Write a function that accepts a pointer to a C-string as its argument. The function should
    count the number of times the character ‘w’ occurs in the argument and return that number.

Answer 31

int wCount(char str)
{
int num = 0;
while (str != ‘\0’)
{
if (*str == ‘w’)
num++;
}
return num;
}

Question 32

32. Assume that str1 and str2 are string class objects. Write code that displays “They are the
    same!” if the two objects contain the same string.

Answer 32

if (str1 == str2)
cout &laquo_space;“They are the same!”;

Question 33

Character testing functions, such as isupper , accept strings as arguments and test each
character in the string

Answer 33

false

Question 34

If toupper ’s argument is already uppercase, it is returned as is, with no changes.

Answer 34

true

Question 35

If tolower ’s argument is already lowercase, it will be inadvertently converted to
uppercase

Answer 35

false

Question 36

The strlen function returns the size of the array containing a string.

Answer 36

false

Question 37

If the starting address of a C-string is passed into a pointer parameter, it can be
assumed that all the characters, from that address up to the byte that holds the null terminator, are
part of the string

Answer 37

true

Question 38

C-string handling functions accept as arguments pointers to strings (arraynames or
pointer variables), or literal strings

Answer 38

true

Question 39

The strcat function checks to make sure the first string is large enough to hold both
strings before performing the concatenation

Answer 39

false

Question 40

The strcpy function will overwrite the contents of its first string argument.

Answer 40

true

Question 41

The strcpy function performs no bounds checking on the first argument.

Answer 41

true

Question 42

42. T F There is no difference between “847” and 847.

Answer 42

false

Question 43

43. char str[] = “Stop”;
    if (isupper(str) == “STOP”)
    exit(0);

Answer 43

The isupper function can only be used to test a character, not a string

Question 44

44. char numeric[5];
    int x = 123;
    numeric = atoi(x);

Answer 44

atoi converts a string to an integer, not an integer to a string

Question 45

45. char string1[] = “Billy”;
    char string2[] = “ Bob Jones”;
    strcat(string1, string2);

Answer 45

The compiler will not allocate enough space in string1 to accommodate both
strings

Question 46

46. char x = ‘a’, y = ‘a’;
    if (strcmp(x, y) == 0)
    exit(0);

Answer 46

strcmp