Deck 22: Bits, Characters, C Strings and Structs

Question 1

__________ is not allowed.

A) Accessing individual bits in a multi-bit bit field.
B) Padding a bit field with bits that cannot be accessed.
C) Having an unnamed bit field.
D) Having a bit field with a zero width.

Answer 1

A

Question 2

Evaluate (00001000 & 11000101) ^ (11110000).

A) 00001101
B) 11000000
C) 00111101
D) 11110000

Answer 2

D

Question 3

The functions of the character-handling library typically manipulate characters as:

A) ints
B) floats
C) longs
D) chars

Answer 3

A

Question 4

Structure variable declarations can be incorporated into a structure definition by placing a comma-separated list of variable names:

A) After struct StructureName and before the left brace.
B) After the left brace and before the member declarations.
C) After the member declarations and before the right brace.
D) After the right brace and before the semicolon.

Question 5

Arrays are:

A) Always passed by reference.
B) Passed by reference unless inside a structure.
C) Passed by reference unless their elements are structures.
D) Always passed by value.

Question 6

Which of the following statements is false?

A) Names for structure types are often defined with typedef to create more readable type names.
B) The statement
Typedef Card* CardPtr;
Defines the new type name CardPtr as a synonym for type Card*.
C) Creating a new name with typedef does not create a new type; typedef simply creates a new type name that can then be used in the program as an alias for an existing type name.
D) C++11 added the keyword using as another mechanism for creating type aliases. The following declaration is equivalent to the typedef in part b):
Using Card* = CardPtr;

Question 7

The isxdigit function would return false on:

A) a
B) A
C) 2
D) g

Question 8

Typedef is used to:

A) Create a type name that is an alias for another type name.
B) Make a struct private.
C) Cast one struct to another type.
D) Initialize struct members.

Question 9

A bit field must be declared as a:

A) int or unsigned.
B) char.
C) float.
D) long.

Question 10

Which of the statements a), b) and c) is false?

A) To create a binary literal, precede a sequence of 1s and 0s with 0b or 0B.
B) You can define a 32-bit mask as
0b10000000'00000000'00000000'00000000
C) The literal in part b) uses C++14's single-quote character to separate groups of digits for readability.
D) All of the above statements are true.

Question 11

Let x be an unsigned int on a machine with 4-byte unsigned ints. What effect does x>>=1;
X<<=1;
Have?

A) There is no effect.
B) The leftmost bit of x is set to 0.
C) The rightmost bit of x is set to 0.
D) Both (b) and (c).

Question 12

Which is the proper way to create a built-in array of structure variables of type Data?

A) MyArray Data[10]
B) Data MyArray[10];
C) Data struct myArray[10];
D) struct MyArray[Data];

Question 13

The main difference between structures and classes is:

A) Whether they default to public or private access.
B) How they access member variables.
C) That classes always require new be used with them while structures do not.
D) There is no difference between structures and classes.

Question 14

For any nonzero 8-bit x, which of the following does not result in zero?

A) x &= (~x)
B) x ^= x
C) x <<= 8
D) x |= x

Question 15

The advantages of using typedef do not include:

A) Making programs more portable by allowing data types to be easily changed to meet system specifications.
B) Making type names shorter.
C) Making programs more readable.
D) Increasing the efficiency of accessing struct member variables.

Question 16

Let Bit1 = Bit2 = 1. Which of the following does not have the same result as the others?

A) Bit1 & Bit2
B) Bit1 | Bit2
C) Bit1 ^ Bit2
D) ~(~Bit2)

Question 17

Which of the following is not a bitwise operator?

A) ^
B) >>
C) ~
D) *

Question 18

Two structure variables of the same type with the same member values, when compared will:

A) Always compare equally.
B) Never compare equally.
C) Sometimes compare equally.
D) Result in a compile error.

Question 19

The most basic unit of data on a computer is the:

A) Bit.
B) Byte.
C) File.
D) int.

Question 20

The number of bits in a bit field is specified with:

A) Parentheses as in bitfield(4)
B) A colon as in bitfield : 4
C) Brackets as in bitfield[4]
D) A dot as in bitfield.4

Question 21

The main difference between the functions atof, atoi and atol is:

A) Their return types.
B) Their arguments.
C) Their header files.
D) Their efficiency.

Question 22

Assuming that string1 = "hello" and string2 = "hello world", which of the following returns 0?

A) strcmp(string1, string2);.
B) strcmp(string1, string2, 6);.
C) Strncmp(string1, string2, 5);.
D) strncmp(string1, string2, 6);.

Question 23

The ___________ function allows characters of one part of a string to be copied into another, overlapping part of the same string.

A) memchr
B) memcmp
C) memcpy
D) memmove

Question 24

Which function would be the most useful for determining if a certain word is contained in a string representing a sentence?

A) strcspn.
B) strchr.
C) strstr.
D) strrchr.

Question 25

Strtok does not:

A) Replace each delimiting character with '\0'.
B) Return a pointer to the token it creates.
C) Completely tokenize the string the first time it is called.
D) Modify the input string.

Question 26

Memcmp would return ___________ for the call memcmp("Hi, how are you?", "Hi, how are things?", 6).

A) 1
B) A positive number.
C) 0
D) A negative number.

Question 27

Which of the following correctly copies the contents of string2 into string1? Assume that string2 is equal to "goodbye" and string1 is equal to "good morning"?

A) strcpy(string1, string2);.
B) strcpy(string1, string2, 6);.
C) Strncpy(string1, string2, 5);.
D) strncpy(string1, string2, 6);.

Question 28

To change the string "ABCDEFGHI" to "aaaaaFGHI" you would use the _________ function.

A) memset
B) memcmp
C) memchr
D) memcopy

Question 29

The strtol and stroul functions do not:

A) Need a header file to be used.
B) Take three arguments.
C) Have the same return types.
D) Have the ability to return data in base 8.

Question 30

What is the output of the following statement? cout << strspn("Cows like to moo.", "Ceik losw");

A) Nothing.
B) 10.
C) 8.
D)
E)