AP Computer Science Principles Unit 7 Test

Parameter -

a variable in a function definition. Used as a placeholder for values
that will be passed through the function.

Argument -

the value passed to the parameter

Return -

used to return the flow of control to the point where the procedure (also
known as a function) was called and to return the value of expression.

MOD -

is the remainder that is left after a number is divided by another number
Usage is to determine if a number is even or odd. If you divide any number by two
and there is no remainder, the number is even! You can use MOD to determine if
a number is divisible by another number.

Procedural Abstraction -

Extracting shared features to generalize functionality is known as (term)

How does Procedural abstraction reduce complexity -

helps improve code readability.
manages complexity by allowing for code reuse.
For example: the function move(id, direction) could be used to move an element in any direction, rather than writing separate functions for each direction.

Library:

a group of functions (procedures) that may be used in creating new
programs

API:

Application Program Interface - specifications for how functions in a library
behave and can be used

A procedure that returns the sum of the values in the file -

A student has a data file containing 10,000 numerical values. The student is writing a program to compute the average of the numbers contained in the file. Which of the following procedures is most likely to be useful in the student's program?

A procedure findNegative, which returns the row number of the first negative value that appears in the column or -1 if there are no negative values. -

A student is writing a program that is intended to replace each negative value in a particular column of a spreadsheet with the value 0. Which of the following procedures is most likely to be useful in the student's program?

A procedure isFound, which takes a word and a text file as input and returns true if the word appears in the text file -

Which of the following procedures would be most useful as part of a program to determine whether a word appears in two different text files?

Which of the following are benefits of procedural abstraction? -

Procedural abstraction makes it easier for people to read computer programs.
Procedural abstraction provides an opportunity to give a name to a block of code that describes the purpose of the code block.

Consider the following procedures.
PROCEDURE proc1(str)
{
DISPLAY(str)
DISPLAY("happy")
}
PROCEDURE proc2(str1, str2)
{
proc1(str2)
DISPLAY(str1)
}
What is displayed as a result of the procedure call proc2("birthday", "to you") ?

to you happy birthday

Assume we have an algorithm used to simulate the results of flipping a coin n times. Two variables used for the algorithm are heads_counter, storing the number of heads we’ve had, and flip_counter, storing the number of flips we’ve made. We want to add on to the algorithm so that at the end we display whether there were an odd or even number of tails.

Here are two algorithms that display whether we have an even or odd number of tails:

Algorithm A: Set the value of num_tails to (flip_counter - heads_counter). If the value of num_tails MOD 2is equal to 0, DISPLAY ("Even"), otherwise DISPLAY ("ODD").

Algorithm B: Set the value of even_flips to (n MOD 2) = 0 and set the value of even_heads to (heads_counter MOD 2) = 0. If even_flips is equal to even_heads then DISPLAY ("EVEN"), otherwise DISPLAY ("ODD").

Both Algorithm A and Algorithm B always calculate the correct answer.

Given the following algorithms, which one uses iteration?
a. Given two numbers display the sum of the numbers.
b. Given a list integers, display the sum of the list
c. Given two variables swap the values of the variables
d. Given a list of integers, display the length of the list.

b. Given a list integers, display the sum of the list

A pizza parlor has an inventory list for their toppings. Which of the following algorithms is LEAST likely to use iteration?

a. Getting a list of all the meat toppings.

b. Getting the first topping in the inventory list

c. Getting a list of all the vegetarian toppings.

d. Reordering their inventory list so that it is alphabetical.

b. Getting the first topping in the inventory list

Procedures A and B are meant to get the minimum value of a list of one or more integers. We have the two procedures below. Which of the following statements is true?

Procedure A

PROCEDURE getMin(list){min ← list[1]FOR EACH item IN list{IF (item < min) {min ← item}}RETURN min}

Procedure B

PROCEDURE getMin(list){min ← list[1]counter ← 1 REPEAT LENGTH (list) TIMES:{counter ← counter + 1item ← list[counter]IF (item < min) {min ← item}}RETURN min}

Procedure A returns the correct minimum value, but Procedure B does not.

This function finds the minimum number in a list. What should <MISSING CODE SEGMENT> be replaced with in order for this function to operate as expected?
function min(numList){ var min = numList[0]; for(var i=0; i<numList.length; i++){ if(numList[i] < min){ <MISSING CODE SEGMENT> } } return min; }
a. numList[i] = min;
b. min = numList[i];
c. min = numList;
d. numList = min;

b. min = numList[i];

Which of the following is true of procedures (functions)? Choose 2.

a. Procedures (functions) make programs less complex by reducing identical code.

b. A procedure (function) must be called once in order to be useful.

c. Procedures (Functions) must return a value (a boolean, number,

d. Updating code is easier if procedures (functions) are used for repeated parts of the program.

a. Procedures (functions) make programs less complex by reducing identical code.d. Updating code is easier if procedures (functions) are used for repeated parts of the program.

Which term refers to a solution to a large problem that is based on the solutions of smaller subproblems.
a. procedural abstraction
b. API
c. modularity
d. library

a. procedural abstraction