functions

Question 1

A function is identified by?

Answer 1

Parenthesis ().

Question 2

Prototype? What is the format?

Answer 2

The declarative piece of the function. It is used like a variable declaration and comes before main or inside of it.

void function(int x);

Question 3

return 0; in the main function does what?

Answer 3

Returns 0 to the operating system of the program to let it know that the program is done executing.

Question 4

Function call

Answer 4

using the function

Question 5

Function Definition

Answer 5

The header and body of the function.

Question 6

Return type?

Answer 6

The type of data that the function returns upon completion

int doStuff()

int is the return type.

Question 7

Body of function

Answer 7

The bracket enclosed section of the function that actually performs the objective.

Question 8

What is the difference between parameters and arguments?

Answer 8

Parameter: 
void function (var1, var2, var3)

Question 9

Void function?

Answer 9

A function of the form:

void function ();

that doesn’t return anything but rather, it simply performs a task. It can take varying parameter types however.

Question 10

A function with a return type terminates at _____ a void function terminates _____

Answer 10

when it encounters a return. It requires a return statement

when it reaches the closing brace

Question 11

Local Variables inside a function ______

Answer 11

Only exist in that function and are lost once the function terminates

Question 12

What is the rule for the parameters of your prototype? What about the definition?

Answer 12

For the prototype you just need to note what type of parameters you’re using.

For the definition you must note the name of the variable and the type.

Question 13

Pass by value?

Answer 13

To pass a function a variable to operate with. This variable is a copy of the original and is terminated once it returns to main. Meaning the original value is unchanged in main.

Question 14

What is the accessibility of local and global variables to functions?

Answer 14

Local variables are only accessible to the functions they are defined in. Local variables can have the same name inside their respective functions.

Global variables are accessible to all functions since they are defined outside all functions.

Question 15

Static variables? How are they used?

Answer 15

Static variables keep their values from a function through multiple calls to the program.

static int variable;

Question 16

Every c++ program must have 1 ______ function?

Answer 16

main

Question 17

How are default arguments applied to a function?

Answer 17

In the prototype just assign the data type a value. The default values must come after those that do not have defaults.

EX:

int function (int = 5, double = 1.2); 
or: int function(int num = 5, double num = 1.2); 

when called, the function defaults to those values and any entered parameters can overwrite the defaults.

Question 18

What is pass by reference and how is it done?

Answer 18

A pass by reference allows a function to change the original value of a variable passed to it from inside the function.

Ex: int dostuff (int &variable)

variable can now be changed from dostuff

Question 19

Function Overloading? How is it done?

Answer 19

Functions can have the same name and type but must have a different parameter listing.

EX:

int function (int); 
int function (int, int);

Question 20

How can a function return an expression?

Answer 20

return value + value2;
return value / value2;
return value * value;

etc

Question 21

A bool function can return

Answer 21

true or false`

Question 22

How is the round function used?

Answer 22

Requires < cmath > header

Accepts a value and returns an int rounded to the nearest whole number.
EX:

cout &laquo_space;round(25.5);

will output 26.

Question 23

What is the exit function?

Answer 23

Requires: < cstdlib >

will terminate the program wherever it is used.

exit(0);

Question 24

test driver

Answer 24

like main

this runs the function

Question 25

functional decompositon

Answer 25

breaks the function down

Question 26

pass by reference in a function

Answer 26

add a & after the data type