Data Structures and Algorithms
What is a data structure? - Answer- An arrangement of data inside a computers
memory or a disk.
Name 5 data types - Answer- BLASH: binary trees, linked lists, arrays, stacks, hash
tables
What do algorithms do? - Answer- Manipulate the data in data structures in various
ways such as sorting.
What is real-world storage data? - Answer- Data structure storage that describes
physical entities external to the computer. Accessed by a programs user.
What are programmer's tools? - Answer- Data structure storage that is accessed by
the program itself. Ex - stacks and queues.
What is real-world modeling? - Answer- Data structures that directly model real-world
situations...think graphs.
What is an object? - Answer- A software bundle of variables and related methods.
What is a class? - Answer- A blueprint that defines an objects variables and
methods.
The keyword "new" is used to do what? - Answer- Create a new object in Java.
An object is often referred to as: - Answer- An instance of a class.
object.method(); is and example of - Answer- Invoking a method for a specific object.
Execution of the program starts where? - Answer- main()
To create an object in Java you must do two things: - Answer- 1. Use the keyword
"new"
2. Store a reference to the object in a variable that is the same type as the class.
So:
Object = new ClassReference();
How do other parts of your program interact with objects? - Answer- By interacting
with an objects methods
What is a constructor? - Answer- A special method that is called automatically
whenever a new object is created. It prepares the object for use.
How is the constructor named? - Answer- It has the same name as the class it
resides in.
, A field of method that is private can only be accessed by - Answer- Methods that are
apart of the same class.
Any outside entity that wants to access data in a class can do so by: - Answer- Using
a method of that class.
What must be added to all input methods for them to work? - Answer- throws
IOException
What does the charAt() method do? - Answer- Returns a character at the specific
position in the string object.
What does the parse.Int() method do? - Answer- Converts the string type into an
integer.
What is an array? - Answer- A container object that holds multiple values of the
same type.
What are the two types of data in java? - Answer- Primitive types (int, char,
boolean,long, double etc) and objects.
Why must you use the key word "new" when creating an array? - Answer- Arrays in
java are treated as objects.
What does the [] operator tell the compiler? - Answer- That we are naming an array
object.
What are the steps to creating an array? - Answer- MRCNL: Main(), Reference,
Create an Array, Number of Items, Loop.
long [] arr is; an example of: - Answer- Referencing an array.
arr = new long [100];is an example of: - Answer- Creating an array.
int nElems = 0; is an example of: - Answer- The number of items in the array .
int x; is an example of: - Answer- A loop creator.
What does the searchKey variable do? - Answer- IT holds the value we are looking
for.
What are the three steps to delete an item in an array? - Answer- 1.Search for the
item
2. Find the item
3. Move the items with a higher index value down to fill the "hole"
First two steps of object-oriented approach? - Answer- 1. Separate the data structure
storage from the rest of the program(now called the user).
2. Improve the communication between the storage structure and the user.
What is a data structure? - Answer- An arrangement of data inside a computers
memory or a disk.
Name 5 data types - Answer- BLASH: binary trees, linked lists, arrays, stacks, hash
tables
What do algorithms do? - Answer- Manipulate the data in data structures in various
ways such as sorting.
What is real-world storage data? - Answer- Data structure storage that describes
physical entities external to the computer. Accessed by a programs user.
What are programmer's tools? - Answer- Data structure storage that is accessed by
the program itself. Ex - stacks and queues.
What is real-world modeling? - Answer- Data structures that directly model real-world
situations...think graphs.
What is an object? - Answer- A software bundle of variables and related methods.
What is a class? - Answer- A blueprint that defines an objects variables and
methods.
The keyword "new" is used to do what? - Answer- Create a new object in Java.
An object is often referred to as: - Answer- An instance of a class.
object.method(); is and example of - Answer- Invoking a method for a specific object.
Execution of the program starts where? - Answer- main()
To create an object in Java you must do two things: - Answer- 1. Use the keyword
"new"
2. Store a reference to the object in a variable that is the same type as the class.
So:
Object = new ClassReference();
How do other parts of your program interact with objects? - Answer- By interacting
with an objects methods
What is a constructor? - Answer- A special method that is called automatically
whenever a new object is created. It prepares the object for use.
How is the constructor named? - Answer- It has the same name as the class it
resides in.
, A field of method that is private can only be accessed by - Answer- Methods that are
apart of the same class.
Any outside entity that wants to access data in a class can do so by: - Answer- Using
a method of that class.
What must be added to all input methods for them to work? - Answer- throws
IOException
What does the charAt() method do? - Answer- Returns a character at the specific
position in the string object.
What does the parse.Int() method do? - Answer- Converts the string type into an
integer.
What is an array? - Answer- A container object that holds multiple values of the
same type.
What are the two types of data in java? - Answer- Primitive types (int, char,
boolean,long, double etc) and objects.
Why must you use the key word "new" when creating an array? - Answer- Arrays in
java are treated as objects.
What does the [] operator tell the compiler? - Answer- That we are naming an array
object.
What are the steps to creating an array? - Answer- MRCNL: Main(), Reference,
Create an Array, Number of Items, Loop.
long [] arr is; an example of: - Answer- Referencing an array.
arr = new long [100];is an example of: - Answer- Creating an array.
int nElems = 0; is an example of: - Answer- The number of items in the array .
int x; is an example of: - Answer- A loop creator.
What does the searchKey variable do? - Answer- IT holds the value we are looking
for.
What are the three steps to delete an item in an array? - Answer- 1.Search for the
item
2. Find the item
3. Move the items with a higher index value down to fill the "hole"
First two steps of object-oriented approach? - Answer- 1. Separate the data structure
storage from the rest of the program(now called the user).
2. Improve the communication between the storage structure and the user.
