Set and Map Operations in Java and Python

What must be true about parent node values in a heap structure?

Which method retrieves but does not remove the root of a heap in Java?

What occurs when attempting to dequeue from an empty Java PriorityQueue?

What is the method to dequeue in Python's PriorityQueue?

Which of the following is the correct method to enqueue an element into a PriorityQueue in Java?

What describes the main feature of a Max Heap?

Which class in Java provides the implementation of PriorityQueue?

What operation combines all elements of two sets without duplication?

What is the result of the operation {1, 3, 5} ∩ {3, 4, 5}?

Which function in Python checks if a PriorityQueue is empty?

Which set implementation in Java stores elements in natural sorted order?

What is the method to check if a set is a subset of another set in Python?

What type of key-value pair storage does a HashMap use in Java?

Which operation determines elements only in the first set but not in the second?

What is the result of {1, 2, 3} ∪ {4, 5} in Python?

Which Java Map implementation maintains insertion order?

Set Operations and Implementations

Union: Combines all elements of two sets without duplicates
Intersection: Returns common elements in two sets
Difference: Returns elements in the first set but not in the second set
Subset: A set containing all elements from another set (issubset() in Python)
HashSet (Java): Stores elements without maintaining order; fast lookups
TreeSet (Java): Stores elements in natural sorted order
LinkedHashSet (Java): Stores elements in insertion order.
Methods for Sets:
- issubset(): Python method to check if a set is a subset of another set

Key-Value Pair Storage

HashMap (Java): Uses a hash table for storing key-value pairs
Dictionary (Python): Key-value pairs
- del: Removes a key-value pair from a Python dictionary.
Map Methods (Java):
- replace(): Replaces the value of a key in a Java Map.
- get(): Retrieves the value associated with a key.
- put(): Adds a key-value pair or replaces the value.

Heap Data Structures

Min Heap: Parent nodes are smaller than or equal to child nodes
Max Heap: Parent nodes are larger than or equal to child nodes
PriorityQueue (Java): Implements a priority queue; offer() enqueues, poll() dequeues the head.
Heap Methods (Java):
- poll(): Removes and returns the head of the queue (lowest priority in a min-heap).
- peek(): Retrieves the head without removing it.
PriorityQueue (Python): Use the queue library and the put() method to add. get() dequeues.
Heap Initialization (Java): new PriorityQueue() to create an empty priority queue.
PriorityQueue (Python): Use the heapq library to use a heap-based priority queue.

Other Data Structures

Set Initialization (Python): {"a", "b", "c"} initializes a set with the given values.
Sorted Order in Java: TreeSet ensures elements are stored in natural sorted order.
Insertion Order in Java: LinkedHashMap maintains insertion order. HashMaps do not.
Retrieving Keys (Java Map): keySet() retrieves all keys.
Removing (Del key name): del is used to delete items in dictionaries and lists in Python.

This quiz covers essential set operations and implementations in Python and Java, including union, intersection, and difference, as well as data structures like HashSet, TreeSet, and HashMap. Test your knowledge on how these sets and maps function, including relevant methods and key concepts.