Review: Mix 7

A programmer is developing a word game. The programmer wants to create an algorithm that will take a list of words and return a list containing the first letter of all words that are palindromes (words that read the same backward or forward). The returned list should be in alphabetical order. For example, if the list contains the words ["banana", "kayak", "mom", "apple", "level"], the returned list would contain ["k", "l", "m"] (because "kayak", "level", and "mom" are palindromes). The programmer knows that the following steps are necessary for the algorithm but is not sure in which order they should be executed. Executing which of the following sequences of steps will enable the algorithm to work as intended?

I. First shorten, then keep palindromes, then sort

II. First keep palindromes, then shorten, then sort

III. First sort, then keep palindromes, then shorten

• I only

• II only

• I and III

• II and III

Which of the following best describes the purpose of machine learning programs?

• To analyze large data sets, recognize patterns, and make predictions based on data

• To automatically translate algorithms from natural language to machine language

• To determine whether an algorithm can be constructed to answer “yes” or “no” for all possible inputs

• To find approximate solutions to problems that would otherwise require an unreasonably long amount of

  time to solve

A programmer notices the following two procedures in a library. The procedures do similar, but not identical,

things.

Procedure square (n) returns the value n²

Procedure cube (n) returns the value n³

^Which of the following procedures is a generalization of the procedures described above?

• Procedure Add (n, m), which returns the value n + m

• Procedure Fourth (n), which returns the value n⁴

• Procedure Polynomial(n), which returns the value n³ +n²

• Procedure Power (n, m), which returns the value n^m

A student wrote the procedure below, which is intended to ask whether a user wants to keep playing a game.

The procedure does not work as intended.

Which of the following best describes the result of running the procedure?

• The procedure returns true when the user inputs the value "y" and returns false otherwise.

• The procedure returns true when the user inputs the value "n" and returns false otherwise.

• The procedure returns true no matter what the input value is.

• The procedure returns false no matter what the input value is.

Which of the following describes a benefit of using hexadecimal numbers instead of binary numbers to

represent data?

• Hexadecimal can be used to represent fractional values, but binary can only represent integers.

• Hexadecimal can be used to represent a wider variety of data types than binary can, including color and

  geolocation data.

• Hexadecimal is easier for a computer to understand than binary is.

• A hexadecimal representation of a value generally requires fewer digits than a binary representation of the

  same value.