Pankaj Sharma - OpenGenus IQ: Learn Algorithms, DL, System Design

Overview of Graph Colouring Algorithms

In this introductory article on Graph Colouring, we explore topics such as vertex colouring, edge colouring, face colouring, chromatic number, k colouring, loop, edge, chromatic polynomial, total colouring and various algorithmic techniques for graph colouring.

Algorithms

Graph Coloring Greedy Algorithm [O(V^2 + E) time complexity]

In this article, we have explored the greedy algorithm for graph colouring. graph coloring is a special case of graph labeling ; it is an assignment of labels traditionally called "colors" to elements of a graph subject to certain constraints.

Algorithms

Wigderson Graph Colouring Algorithm in O(N+M) time

Wigderson Algorithm is a graph colouring algorithm to color any n-vertex 3-colorable graph with O(√n) colors, and more generally to color any k-colorable graph. In this article, we have explored this wonderful graph colouring article in depth.

Algorithms

Welsh Powell Algorithm for graph coloring in O(N^2) time

Welsh Powell algorithm is used to implement graph labeling; it is an assignment of labels traditionally called "colors" to elements of a graph subject to certain constraints

convex hull

Kirkpatrick-Seidel Algorithm (Ultimate Planar Convex Hull Algorithm)

Algorithm Complexity Applications Reading time: 15 minutes | Coding time: 9 minutes The Kirkpatrick–Seidel algorithm, called by its authors "the ultimate planar convex hull algorithm", is an algorithm for computing the

convex hull

Chan's Algorithm to find Convex Hull

In computational geometry, Chan's algorithm, named after Timothy M. Chan, is an optimal output-sensitive algorithm to compute the convex hull of a set P of n points, in 2- or 3-dimensional space. The algorithm takes O(n log h) time, where h is the number of vertices of the output (the convex hull).

convex hull

Graham Scan Algorithm to find Convex Hull

Graham's Scan Algorithm is an efficient algorithm for finding the convex hull of a finite set of points in the plane with time complexity O(N log N). The algorithm finds all vertices of the convex hull ordered along its boundary. It uses a stack to detect and remove concavities in the boundary.

convex hull

Gift Wrap Algorithm (Jarvis March Algorithm) to find Convex Hull

Gift Wrap Algorithm ( Jarvis March Algorithm ) to find the convex hull of any given set of points. We start from the leftmost point (or point with minimum x coordinate value) and we keep wrapping points in a counterclockwise direction. Find pseudocode, implementations, complexity and questions

convex hull

Divide and Conquer algorithm to find Convex Hull

Divide and Conquer algorithm to find Convex Hull. The key idea is that is we have two convex hull then, they can be merged in linear time to get a convex hull of a larger set of points. It requires to find upper and lower tangent to the right and left convex hulls C1 and C2

convex hull

Quick Hull Algorithm to find Convex Hull

Quickhull is a method of computing the convex hull of a finite set of points in the plane. It uses a divide and conquer approach. It was published by C. Barber and D. Dobkin in 1995. average case complexity is considered to be Θ(n * log(n))

double ended queue

Double Ended Queue (Deque)

A double ended queue also called as deque (pronounced as ‘deck’ or ‘dequeue’) is a list in which the elements can be inserted or deleted at either end in constant time.