Cit 120 Chapter 2 Notes

Front 1

What is a line that starts with # called?

Back 1

preprocessor directive

Front 2

What are namespaces used for?

What does namespace std do?

Back 2

namespaces organize the names of program entities

namespace std declares that the program will be accessing entities whose names are part of the namespace called std. In order for programs use the entities in iostream, it must have access to the std namespace

Front 3

What is the purpose of int main()

Back 3

marks the beginning of a function

Front 4

What is a function? How do you know it's a function?

Back 4

A function is a group of one or more programming statements that collectively has a name

nameoffunction() <-- parentheses indicate it's a function

Front 5

Is C++ case-sensitive?

Back 5

YES

main != Main

m and M are entirely different characters

Front 6

All statements that make up a function are enclosed in a set of

Back 6

braces { }

Front 7

"Programming is great fun!"

What is the group of characters inside the quotation marks called?

Back 7

string literal or string constant

Front 8

What does each of these mean:

// # < > ( ) { } " " ;

Back 8

//Comment #preprocessor directive <encloses a file name when used with #include > ( )used in name a function {group of statements, like contents of a function} "string of characters" end of complete programming statement;

Front 9

What type of output does cout produce?

Back 9

Console output (in terminal as opposed to a window)

Front 10

cout is a stream object. What does this mean?

What is << ?

Back 10

Stream object: works with streams of data

<< stream insertion operator

Front 11

Unless you specify otherwise, how it the information sent to cout displayed?

Back 11

In a single stream (on a single line)

Front 12

What are two ways to instruct cout to start a new line?

Back 12

stream manipulator: endl creates a new line

i

nsert an escape sequence: \followed by one or more control characters. \n is the newline escape sequence. Must be in quotation marks

Front 13

What does each of these escape sequences mean:

\n \t \a \b \r \\ \' \"

Back 13

\n - newline \t - tab \a - alarm \b - cursor backs up one \r - cursor goes to beginning of next line \\prints backslash \' prints ' \" prints "

Front 14

Why is iostream included?

Back 14

input-output stream library. allows program to compile cout and cin

Front 15

What are variables? What are literals?

Back 15

Variables represent storage locations in the computer's memory.

Literals are constant values that are assigned to variables. Literals are also called constants. A literal is a piece of data written directly into the program's code

Front 16

What is included in a variable definition?

Back 16

variable's name and the type of data the variable will hold

Front 17

What is included in a variable assignment?

Back 17

variable name = value;

Front 18

What happens when a variable is sent to cout vs. a string literal?

Back 18

contents of variable are printed

characters inside quotations are printed

Front 19

Before numbers can be displayed on the screen they must first be converted to strings. Fortunately....

Back 19

cout handles the conversion automatically

Front 20

What is an identifier?

Back 20

programmer-defined name that represents some element of a program. do not use C++ key words. name should reflect use.

Front 21

What are three rules for using identifiers?

Back 21

First character must be a-z, A-Z, or _

After the first character, any letters, numbers, or _ can be used

Uppercase and lowercase characters are distinct. ItemsOrdered != itemsordered

Front 22

What kind of data can integer variables hold?

Back 22

Whole numbers

Front 23

What are considerations for selecting a numeric data type?

Back 23

- largest and smallest numbers that may be stored in the variable

- how much memory the variable uses

- whether the variable stores signed or unsigned numbers

- the number of decimal places of precision the variable has

Front 24

What does unsigned mean?

Back 24

nonnegative only

short int: [-32768, 32767]

unsigned short int: [0, +65535]

Front 25

How do you abbreviate each of these:

short int, unsigned short int, int, unsigned int, long int, unsigned long int, long long int, unsigned long long int

Back 25

Remove int from each (except just int)

Front 26

What do you do if you want an integer literal to be treated as a long long int?

Back 26

append LL at the end of the number

long long amount;

amount = 32LL;

Front 27

How do you express hexadecimal numbers in C++? Octal numbers?

Back 27

Hexadecimal: 0x22 (precede number with 0x)

Octal: 022 (precede number with 0)

Front 28

What is the char data type used for? How are character literals assigned?

Back 28

stores individual characters

enclose the character in ' '

char letter='n';

don't confuse string literals " " and char literals ' '

Front 29

When you work with characters, what are you actually working with?

Back 29

Numbers

ASCII: American Standard Code for Information Interchange

Front 30

How does C++ know how long a string literal is?

Back 30

Stores a null terminator/null character ( \0 ) at the end

Front 31

What needs to be included to use the string class?

Back 31

#include <string>

Front 32

What are floating-point data types used for?

Back 32

used to define variables that can hold real numbers

floating-point numbers allow for fractional values

Front 33

What are the three floating point data types?

Back 33

float (single precision)

double (double precision)

long double (longest)

Front 34

What's an easy way to write large numbers?

Back 34

E notation

(similar to scientific notation)

Front 35

How can you force a literal to be stored as a float? As a long?

Back 35

append an F to it

e.g., 1.2F

Append an L

Front 36

What happens when a floating-point value is assigned to an integer variable?

Back 36

the fractional part is truncated

Front 37

What are Boolean (bool) variables set to?

Back 37

true or false

Front 38

How do you determine the size of a data type on any system?

Back 38

sizeof(nameofdatatypeyouwantthesizeof) operator

Front 39

What is assignment? What is initialization?

Back 39

Assignment operation assigns/copies a value into a variable

int x;

x=4;

Initialization: value is assigned to a variable as part of the variable's definition

int x=4;

Front 40

What is the auto key word used for?

Back 40

use auto instead of a data type. compiler will determine data type from initialization value

Front 41

Define scope of a variable

Back 41

variable's scope: part of the program that has access to that variable

variable must be defined before it is used

Front 42

How are unary, binary, and ternary operators defined?

Back 42

define by the number of operands they require

-7 is unary

7*8 is binary

Front 43

What is the % operator called? What is it used for?

Back 43

%: modulus operator

only works with integer operands. returns the remainder of integer division

Front 44

How do you write multi-line comments in C++? Single line?

Back 44

//single line

/* multi-line

comments */

Front 45

What is a named constant?

Back 45

it's like a variable, but its content is read-only and cannot be changed while the program is running

const double InterestRate = 0.09;

Front 46

What does programming style refer to?

Back 46

The way source code is visually arranged