Lecture 2

Question 1

Cin

Answer 1

Streams user input from the console to the computer.&raquo_space; stream operator is used after to denote information is streamed from console. Info is input in the order it is typed (first thing user types goes into first input, etc.)

Question 2

++ and +=

Answer 2

Increment operator increments by one. ++ is placed before or after the variable; before the variable increments before other parts on the line of code are executed and after does it after. += is placed after the variable and increments by whatever is placed after the +=

Question 3

Computations

Answer 3

Mathematical calculations.

Handled by the processor.

Question 4

Variable Declaration

Answer 4

Type and name of a variable followed by a semicolon.

Tells the computer to reserve a type of memory for a variable of a specific name. Whenever that variable is referred to in the code, it will use the information stored in the part of the memory designated for that variable. You can declare all variables of a certain type on one line.

Question 5

Variable assignment

Answer 5

Variable name followed by an equal sign, the initial information assigned to that variable, and a semiclon at the end.

Variables can be reassigned different information and can be assigned on the same line as variable declaration. It is good to set an initial value when declaring a variable. Equal sign in variable assignment is assignment operator, not equal operator.

Question 6

Variable name rules

Answer 6

1. Name can include numbers, letters, and the underscore symbol.
2. Names must start with a letter
3. Names must not use other names reserved for commands or other parts of code

Question 7

For main parts of code and their corresponding computer hardware

Answer 7

Input and output -> user interface
Variables -> memory
Computations -> computer processor

Question 8

Variable

Answer 8

A section of memory that a computer program allows you to use to store information. When a variable name is referenced in a program, the program uses the information stored in that variable “box”

Question 9

Tips for naming a variable

Answer 9

Choose something that gives you a clear idea of what the variable is and is not too long or too short. It is also helpful to format your variables similarly.

Question 10

Float

Answer 10

Floating point variable type. Is a number with a decimal because the decimal can move/float around.

Question 11

Int

Answer 11

Integer type variable. Is an integer/whole number.

Question 12

+

Answer 12

Addition operator

Question 13

-

Answer 13

Subtraction operator

Question 14

*

Answer 14

Multiplication operator

Question 15

/

Answer 15

Division operator

Question 16

Division rules

Answer 16

The result of division is the quotient only. Any remainder will be truncated.

Question 17

%

Answer 17

Modulus operator. Gives the remainder in a division operation.

Question 18

Computation rules

Answer 18

When computations are done with integers, the result will be truncated so it is an integer. It does not round.

Question 19

Memory

Answer 19

Made up of spots that can hold either 1s or 0s. Certain number of spots can be designated for a variable. A piece of information can be made up of multiple 1s and 0s.

Question 20

Tips for writing good code

Answer 20

Write code that is easy to understand for anyone. Pick variable names that helps identify what the variable is.