BJC U5L1d2 Traversing a List

Open Ended

Think, don't talk. Answer doesn't have to be long.

​You'll answer on the next slide

Fill in the Blanks

Which works, which doesn't? You'll answer on the next slide.

Multiple Choice

Don't discuss yet!

Which of those procedures work as expected for any lists?

• A

• B

• Both

• Neither

Multiple Choice

When will "Error. Invalid entry." be displayed?

• When a>b is true

• When a>b is false

• Always

• Never

Multiple Choice

Write it out!

What is the displayed on the stage?

• [-1, 0, 1, 4]

• [-1, 2, 4, 5]

• [-1, 1, 3, 4]

• None of the above

numList: [-1, 0, 1, 2, 3, 4, 5]

delete item 2: ​[-1, 1, 2, 3, 4, 5]

del item 3: ​[-1, 1, 3, 4, 5]

del item 5: ​[-1, 1, 3, 4]​

Trace the code

Think, don't say:

How do we fix this​?

Moral of the story?

Multiple Choice

A computer model is ...

• a premier computer entered by a manufacturer in a competition

• can simulate what might happen in a situation

• requires a hypothesis

• a simulation

Multiple Choice

A simulation is ...

• a model

• a hypothesis

• when you exercise a model using values for input parameters

• an algorithm with a hypothesis

Multiple Choice

A hypothesis is ...

• a type of an algorithm

• the solution to a model

• tentative explanation to be tested by further investigation

• the results of a simulation

Multiple Choice

A binary search ...

• is faster than a linear search

• works less efficiently with an unsorted list

• accesses all the items in a list

• requires a sorted list

Multiple Choice

Assume code works as intended (uses list library in Snap). What will be the value of list3 after this script is executed?

• 1 1 2 2 3 3 4 4

• 1 2 3 4

• 4 4 3 3 2 2 1 1

• 4 3 2 1

Multiple Choice

The "flip a coin" procedure demonstrates ...

• hypothesis

• linear search

• binary search

• abstraction

Multiple Choice

The instruction "change (head_count) by (flip a coin()) can be replaced by which of the following and still produce the same result?

• set (head_count) to (head_count + flip a coin)

• set (head_count) to (flip a coin())

• set (head_count) to (head_count + 1)

• set (head_count) to (1)

Multiple Choice

What is x?

numbers[x] <-- 3

(left arrow)

• an element of the list

• may be any primitive data type supported by the programming language

• must be a whole number

• is set to 3

Multiple Choice

A binary search is the fastest when ...

• You only need to search the list a single time

• The list in question is very short

• You perform lots of searches for different values, with no duplicates in the list

• You perform lots of searches for different values, some of which repeat in the list

Multiple Choice

A non-traditional data source used when monitoring a disease spread is ...

• the # of people infected by disease as reported by doctors

• the # of prescriptions for disease reported by pharmacists

• the # of zombies reported in the area

• the # of people googling the disease in a given area

Multiple Choice

Should you end English sentences in a preposition like "with" or "to"?

EX: Which table is "dept_name" a field in?

• Yes

• No

• Avoid in formal writing because it's technically grammatically wrong

• Avoid in formal writing to avoid offending people who don't know grammar