C++ Primer - Chapter 1 (Getting Started)

Question 1

A function definition consists of what four parts?

Answer 1

A return argument, a function name (identifier), a parameter list (which may be empty), and a function body.

Question 2

What is an “argument”?

Answer 2

A value passed to a function.

Question 3

What does “assignment” do?

Answer 3

Obliterates an object’s current value and replaces that value by a new one.

Question 4

What is a “block” of code?

Answer 4

Sequence of zero or more statements enclosed in curly braces.

Question 5

What is a “buffer”? Give an example of where a buffer is used.

Answer 5

A region of storage used to hold data. IO facilities often store input (or output) in a buffer and read or write the buffer independently from actions in the program.

Question 6

What is “cerr”?

Answer 6

An ostream object tied to the standard error, which often writes to the same device as the standard output.

Question 7

What is a “character string literal”?

Answer 7

A sequence of characters enclosed by double quotation marks.

Question 8

What is “cin”?

Answer 8

An istream object used to read from the standard input.

Question 9

What is “clog”?

Answer 9

An ostream object tied to the standard error.

Question 10

What is the edit-compile-debug process?

Answer 10

The process of getting a program to execute properly.

Question 11

What is an end-of-file?

Answer 11

System-specific marker that indicates that there is no more input in a file.

Question 12

What is an “expression”?

Answer 12

The smallest unit of computation. An expression consists of one or more operands and usually one or more operators. Expressions are evaluated to produce a result.

Question 13

What is a header?

Answer 13

Mechanism whereby the definitions of a class or other names are made available to multiple programs.

Question 14

What does it mean to “initialise”?

Answer 14

Give an object a value at the same time that it is created.

Question 15

What is a stream manipulator?

Answer 15

An object, such as std::endl, that when read or written “manipulates” the stream itself.

Question 16

What is a method?

Answer 16

A synonym for member function.

Question 17

What is a namespace?

Answer 17

Mechanism for putting names defined by a library into a single place.

Question 18

What is a parameter list?

Answer 18

Part of the definition of a function; a (possibly empty) list that specifies what arguments can be used to call the function.

Question 19

What is a source file?

Answer 19

A file that contains a C++ program.

Question 20

What is an uninitialised variable?

Answer 20

A variable that is not given an initial value.

Question 21

What is the () operator called?

Answer 21

Call operator. A pair of parentheses “()” following a function name.

Question 22

What is the :: operator called?

Answer 22

Scope operator.

Question 23

Define “#include”

Answer 23

A directive that makes code in a file available to a program.

Question 24

Name the four IO objects defined in the iostream library.

Answer 24

cin, cout, cerr, clog

Question 25

What is a stream?

Answer 25

A sequence of characters read from or written to an IO device.

Question 26

Is the result of an ostream or istream output the left or right operand of the&raquo_space; operator?

Answer 26

Left-hand operand.

Question 27

What is the endl operator?

Answer 27

A stream manipulator; it ends the current line and flushes the buffer.

Question 28

Where are include directives typically written?

Answer 28

At the top of a file.

Question 29

What does a return value of zero from main() indicate? What does a non-zero value indicate? What does this non-zero value typically tell you?

Answer 29

A return value of 0 indicates program success. A return value >0 indicates program failure; the value is normally the type of error encountered.

Question 30

Why should std::cout statements used during debugging always use std::endl and not “\n”?

Answer 30

Statements not using the std::endl manipulator won’t get immediately flushed to the output, and may instead be left sitting in the buffer when the program fails.

Question 31

What is the general syntax of a while loop?

Answer 31

while (condition){ statement }

Question 32

What is the general syntax of a for loop?

Answer 32

for (init-statement; condition; expression){ body }

Question 33

How can an unknown number of inputs be read in to a C++ program?

Answer 33

With a while loop of the form:while (std::cin&raquo_space; input){ body }

Question 34

What happens to an istream when it hits an end-of-file?

Answer 34

It becomes invalid; causing conditions to return the value false.

Question 35

What is the difference between ‘a’ and “a” in C++?

Answer 35

‘a’ is a character and “a” is a string literal which is represented with two characters: ‘a’ and ‘\0’.

Question 36

What character is automatically appended to the end of a string?

Answer 36

The ‘\0’ character.

Question 37

If data is held by cout in the buffer and cin is called, what happens to the data?

Answer 37

By default, reading cin flushes cout, forcing the buffer to be written. Note: cout is also flushed when the program ends normally.

Question 38

How are variables of class type initialised if no initial value is specified?

Answer 38

It is default initialised using the class definition.

Question 39

How is a variable of built-in type, which is defined outside a function, initialised when no initial value is provided?

Answer 39

Variables of a built-in type defined outside a function are default initialised to zero.

Question 40

True or false? It is not an error to use the value of an uninitialised variable.

Answer 40

False. It is an error to try to use the value of an uninitialised variable.

Question 41

Are writes to cerr are buffered?

Answer 41

No. By default, writes to cerr are not buffered.

Question 42

What is cerr typically used for?

Answer 42

cerr is typically used for error messages or other output that is not part of the normal logic of the program.

Question 43

Are writes to clog buffered?

Answer 43

Unlike cerr, writes to clog are, by default, buffered.

Question 44

How is a header used in a program?

Answer 44

A program uses a header through a #include directive.

Question 45

Why is a namespace helpful?

Answer 45

Namespaces help avoid inadvertent name clashes.

Question 46

What is the call operator used for?

Answer 46

The call operator causes a function to be invoked. Arguments to the function may be passed inside the parentheses.

Question 47

What is clog typically used for?

Answer 47

clog is usually used to report information about program execution to a log file.

Question 48

How is a variable of built-in type, which is defined inside a function, initialised when no initial value is provided?

Answer 48

Variables of a built-in type defined inside a function are uninitialised.