AP Classroom 6.1-6.4 Test Flashcards

Questions and Answers

What can replace `longest` in the method `countTarget` so that the method works as intended?

String longest = words;

Is there any precondition necessary for the method `findAvg` to work as intended?

True

What statement can be used to replace the empty statement in the `reverse` method?

newArr[k] = arr[arr.length - k - 1];

What can replace the empty statement in the `twoInARow` method so that the method works as intended?

for (int k = 0; k < arr.length - 1; k++) Signup and view all the answers

Why doesn't the provided code segment produce the intended output regarding memory?

An error occurs during compilation because the getScreenWidth and getScreenHeight methods are not defined for the Computer object myPhone. Signup and view all the answers

Why does the code segment not produce the intended output AB?

Method m2 is executed from the subclass instead of the superclass because obj1 is instantiated as a C2 object. Signup and view all the answers

Why does the code segment involving `Bike` and `EBike` not compile?

The getNumOfWatts method is not found in the Bike class. Signup and view all the answers

Study Notes

Method Functionality and Corrections

countTarget Method: Intended to return the frequency of target in arr. Requires correction in implementation.
findAvg Method: Calculates arithmetic mean of an integer array; no preconditions necessary for execution.
reverse Method: Designed to return a reversed array from the input arr. Correct logic to reverse must be implemented.

Code Output Comparisons

Array Printing Code: The code snippet using enhanced for-loop prints values directly. An alternative using index-based access must ensure the correct array element is accessed.
Output Consistency: Only specified code segment III reproduces the original output of printing array elements.

Logic Implementation in Conditional Checks

twoInARow Method: A proper iteration is required to detect consecutive equal elements in an array, necessitating adjustment in the loop index range.

Class and Inheritance Issues

Computer and Smartphone Classes: Compilation error arises from trying to access subclass-specific methods from a superclass reference.
Method Overriding: In subclass C2 of class C1, overriding m2 leads to different output than expected when called through superclass reference.

Object Creation and Method Access

Bike and EBike Classes: Attempt to print getNumOfWatts() on a Bike reference results in a compilation error, as the method does not exist in the superclass.

General Principles

Methods must align correctly with expected outputs and constructors.
Understanding superclass versus subclass method access is crucial for avoiding compilation errors and achieving intended functionalities.

Description

Test your understanding of concepts covered in AP Classroom sections 6.1, 6.2, 6.3, 6.4, and 9.6. This quiz includes example questions and flashcards to help reinforce key programming methods and logic. Improve your coding skills and prepare for your exams with these targeted questions.