What is a Queue? A Queue is an abstract data type that serves as an ordered collection of elements. A simple queue typically has several operations: push(item) - adds an item to the tail pop() - removes and returns an item from the head These operations make a queue a FIFO (First In, First Out) data structure. Implementation There are two ways to implement a queue. The first and simplest (but less efficient) way is by using an array and basic operations:...
What is an Adjacency List? An Adjacency List helps store a list of connections between each vertex in a finite graph. Vertex Connects with 0 1 1 0, 2, 3 2 1, 3 3 1, 2 Implementation The addEdge method takes vertices as input and adds an edge to the adjacency list. In this example, the adjacency list is represented as a dictionary that maps vertices to a set of all connected vertices....
What is a graph? A graph is an abstract data type that represents vertices and edges that connect those vertices. Source Implementation A graph can be represented as a matrix with edges connecting each pair of vertices. For example, a graph with vertices 0, 1, 2, 3, 4 and edges between them can be represented as a matrix: 0 1 2 3 4 0 false true false false true 1 true false true true true 2 false true false true false 3 false true true false true 4 true true false true false In Swift, you can use a list of lists (2D array) to represent the matrix:...
What is Breadth First Search? Breadth-first search (BFS) is an algorithm for traversing tree or graph data structures. It starts at the root and explores all the neighboring nodes at the current depth before moving on to nodes at the next depth level. Source Implementation The implementation of BFS may vary depending on the problem. The main idea of BFS is: It has a visited array that collects all elements that have already been visited....
What is Backtracking? Backtracking is a class of algorithms for finding solutions to complex problems. A backtracking algorithm uses recursion and is based on depth-first search (DFS). Depth First Search (DFS) Depth First Search (DFS) is an essential part of backtracking. DFS is an algorithm for traversing or searching tree or graph data structures. The algorithm starts at the root node (or an arbitrary node in the case of a graph) and explores as far as possible along each branch before backtracking....