Chapter 5 (Loops)

Question 1

One set of instructions that operate on multiple, separate sets of data

Answer 1

Loop

Question 2

This keyword starts the loop body and precedes any statements that execute when the tested condition is True.

Answer 2

While

Question 3

What keyword ends the “while” loop structure?

Answer 3

Endwhile

Question 4

What does the loop control variable do?

Answer 4

Manages the number of repetitions a loop performs.

Question 5

What are the 3 actions that should occur when using a loop control variable:

Answer 5

1. INITIALIZE the variable before entering the loop.
2. TEST the variable to see if the result is True, before entering the loop.
3. Set conditions which allow the variable to be ALTERed within the body of the loop.

Question 6

What is the significance of making the loop control variable alterable within the body of the loop?

Answer 6

It allows the tested condition to return as false, which will make the loop end (eventually).

Question 7

Initializing the loop control variable is essentially providing the loop with a ______ ____.

Answer 7

starting value

Question 8

The 3 separate actions concerning a loop control variable prevents ______ _____.

Answer 8

infinite loops

Question 9

What are 2 common loop control variable types?

Answer 9

1. a counter

2. a sentinel value

Question 10

Sentinel values as a loop control variable are used to create what type of loop?

Answer 10

indefinite

Question 11

These loops execute a predetermined number of times.

Answer 11

Definite loops

Question 12

A counter is any numeric value that counts the number of times an event has occurred. What is the best number to start a counted loop at?

Answer 12

0

Question 13

This naturally lends itself to definite loops with a starting value/counter of 0

Answer 13

array manipulation

Question 14

Is starting a counter loop at 0 necessary?

Answer 14

No, but it is encouraged.

Question 15

Counted loops are a program that track the number of loop repetitions by counting them. What is another name for counted loops?

Answer 15

Counter-controlled loops.

Question 16

These loops perform a varying amount of times.

Answer 16

Indefinite loops

Question 17

<> is a ______ symbol

Answer 17

placeholder

Question 18

What is the name of this placeholder symbol: <>

Answer 18

Not-equal-to-operator

Question 19

Evaluates as True when its operands are not equivalent/identical

Answer 19

<>

Question 20

What are loops within loops?

Answer 20

Nested loops

Question 21

The nested loop contains:

Answer 21

At least 1 outer loop, and at least 1 inner loop

Question 22

An inner loop goes through all of its iterations each time that an outer loop goes through how many iterations?

Answer 22

One

Question 23

# of inner loop iterations * # of outer loop iterations
The above is...

Answer 23

the formula for the total number of iterations executed by a nested loop.

Question 24

Another phrase for the “for statement”

Answer 24

For loop

Question 25

For statements are used for what type of loop?

Answer 25

Definite loops

Question 26

What is the keyword that ends for statements?

Answer 26

endfor

Question 27

Step value is...

Answer 27

the amount by which a for loop control variable changes.

Question 28

The step value can be any number. If the step value is positive or negative this implies ______ or ______ a value.

Answer 28

incrementing, decrementing

Question 29

The for loop provides a convenient shorthand for what type of loop?

Answer 29

a While loop

Question 30

What allows a for loop to be a shorthand version of a while loop?

Answer 30

They are both used for definite loops where the loop control variable progresses from a known starting value to a known ending value IN EQUAL STEPS.

Question 31

Which loop is particularly useful for processing arrays?

Answer 31

For loop

Question 32

What does the expression count++ do in a for loop?

Answer 32

It increases count by 1.

Question 33

The loop control variable is tested before each iteration in a...

Answer 33

Pretest loop

Question 34

What is the significance of a pretest loop?

Answer 34

It allows it so that a loop body might never execute, because the evaluation controlling the loop might be false the first time it is made.

Question 35

The loop body executes at least once in this type of loop

Answer 35

Posttest loop

Question 36

In a posttest loop, the loop control variable is not tested until after the 1st ______

Answer 36

iteration.

Question 37

What is another name for the posttest loop?

Answer 37

do while loop

Question 38

In a do while loop, the action you "do" _______ testing the condition.

Answer 38

precedes

Question 39

a ______ followed by a pretest while loop is the equivalent of a do while loop.

Answer 39

sequence

Question 40

What is the significance of these two characteristics? 1. The loop-controlling evaluation must provide either the entry to or exit from the structure. 2. The loop-controlling evaluation provides the ONLY entry to or exit from the structure

Answer 40

These are the characteristics all structured loops (both pretest and posttest) have in common.

Question 41

A variable used to gather values, similar to a counter that you use to count loop iterations

Answer 41

Accumulator

Question 42

What are the 3 actions that must be taken with an accumulator?

Answer 42

1. INITIALIZE it to 0 2. ALTER the accumulator for every dataset processed 3. OUTPUT the accumulator's value at the end of all processing.

Question 43

The accumulator variable is most often altered by using _______.

Answer 43

Addition

Question 44

Variables only exist during an _________ of the program.

Answer 44

execution

Question 45

These contain only totals, and have no data for individual records.

Answer 45

Summary reports

Question 46

Programming that tries to prepare for all possible errors before they occur.

Answer 46

Defensive programming

Question 47

What is the function that a loop performs when used to make sure that data is meaningful, useful, is the correct data type, or falls within an acceptable range?

Answer 47

Validate data

Question 48

GIGO stands for

Answer 48

"Garbage in, garbage out"

Question 49

What does GIGO mean?

Answer 49

If your input is incorrect, your output is worthless.

Question 50

Forcing a data item means you ________ incorrect data by setting the variable to a specific, predetermined value.

Answer 50

override

Question 51

Using the module's results without understanding its internal statements means employing a...

Answer 51

Black box variable

Question 52

What are 3 methods used to ensure data is valid?

Answer 52

1. DISPLAY error message 2. CHOOSE A DEFAULT VALUE before proceeding to the next step with a garbage input. 3. REPROMPT the user for valid input.

Question 53

In the ________ ________, the two logical paths that emerge from testing the condition join together following their actions.

Answer 53

selection structure

Question 54

In a ____ _______, the paths that emerge from a tested condition do not joint together.

Answer 54

Loop structure

Question 55

One of the logical branches that emerges from the _______-_________ _______ eventually returns to the same test, in a loop structure.

Answer 55

structure-controlling decision

Question 56

Selections and loops both begin with a _______ expression and both structures have a body that executes when said expression is evaluated as _____.

Answer 56

Boolean; True

Question 57

When nesting loops, you maintain two ________ loop control variables and alter each at the appropriate time.

Answer 57

separate

Question 58

The ___ statement uses a loop control variable that it automatically initializes, tests, and alters.

Answer 58

For

Question 59

The loop body executes at least one time in a...

Answer 59

posttest loop

Question 60

____ count = 0 to 3 step 1 ______ "Hello" ______

Answer 60

for; output; endfor

Question 61

``` count = 0 _____ count <= 3 output "Hello" count = ______ + __ ________ ```

Answer 61

while; count; 1; endwhile

Question 62

the amount by which a loop control variable changes is called a ____ value.

Answer 62

step

Question 63

for loops and while loops are types of _____ loops.

Answer 63

pretest