DSA prefi

Heap

A complete binary tree where each parent node's value is either higher or lower than the value of its child nodes.

Min Heap

A heap where the value of each parent node is less than or equal to the values of its child nodes.

Max Heap

A heap where the value of each parent node is greater than or equal to the values of its child nodes.

ArrayList

A resizable array implementation in Java from the java.util package used to create heaps.

addAll() method

A method to create a heap with initial values of the Collections class in Java.

Priority Queue

A special type of queue where elements are processed based on their natural or custom order.

PriorityQueue class

A Java class used to implement priority queues from the java.util package.

Enqueue

To add an element to a priority queue using add() or offer().

Dequeue

To remove an element from a priority queue using poll() or remove().

Comparator

An interface in Java used to create a specific ordering for a collection of objects.

comparing() method

A method in the Comparator interface used to define a custom comparison.

Set

A collection of unique elements in Java.

Union of sets

A set that contains all elements in either of two sets (A ∪ B).

Intersection of sets

A set containing only the elements common to both sets (A ∩ B).

Difference of sets

The set that contains elements in A but not in B (A – B).

Subset

Set A is a subset of set B (A ⊂ B) if every element of set A is in set B.

HashSet

A set implementation in Java that stores elements in a hash table without guaranteed order.

TreeSet

A set implementation in Java that stores elements in a sorted order (natural or custom).

LinkedHashSet

A set implementation in Java that maintains insertion order using a hash table and linked list.

containsAll() method

A method used to determine if one set contains all elements of another set.

retainAll() method

A method used to find the intersection of two sets.

removeAll() method

A method used to determine the difference between two sets.

Curly braces in Python

Used to implement sets in Python.

Dictionaries in Python

Maps in Python that use key-value pairs defined with a colon (:) within curly braces.

Map

A set of ordered pairs where elements are known as keys and values.

HashMap

A general-purpose map implementation in Java that does not guarantee order.

TreeMap

A general-purpose map implementation in Java that keeps its keys sorted.

LinkedHashMap

A general-purpose map implementation in Java that maintains insertion order.

put() method

A method used to insert a mapping in a map in Java.

remove() method

A method used to delete the mapping for a key in a map in Java.

replace() method

A method used to replace a key's value in a map in Java.

get() method

A method used to retrieve the value based on the key in a map.

containsKey() method

A method used to check if a map contains a mapping for a specified key.

keySet() method

A method that retrieves all keys of a map.

values() method

A method that retrieves all values of a map.

items() method

A method in Python used to display entries in a dictionary.

issubset() method

A method in Python to determine whether a set is a subset of another set.

Example of creating an empty set in Java

Set a = new HashSet();

Example of initializing a set in Python

a = set(['Mark', 'Nika', 'Mairo', 'Kae'])

Example of checking membership in a dictionary

print('M2' in name_map)