Graphs with negative edge costs, Data Structure & Algorithms

Assignment Help:

We have discussed that the above Dijkstra's single source shortest-path algorithm works for graphs along with non-negative edges (like road networks). Given two scenarios can emerge out of negative cost edges into a graph:

  • Negative edge along non- negative weight cycle reachable from the source.
  • Negative edge along non-negative weight cycle reachable from source.

529_Graphs with Negative Edge costs.png

Figure: A Graph with negative edge & non-negative weight cycle

The net weight of the cycle is 2(non-negative)

437_Graphs with Negative Edge costs1.png

 Figure: A graph with negative edge and negative weight cycle

The net weight of the cycle is 3(negative) (refer to above figure). The shortest path from A to B is not well defined as the shortest path to this vertex are infinite, that means , by traveling each cycle we can reduced the cost of the shortest path by 3, like (S, A, B) is path (S, A, B, A, B) is a path with less cost and so forth.

Dijkstra's Algorithm works only for directed graphs along non-negative weights (cost).


Related Discussions:- Graphs with negative edge costs

Graph, Multilist Representation of graph

Multilist Representation of graph

Graph terminologies, Graph terminologies : Adjacent vertices: Two vert...

Graph terminologies : Adjacent vertices: Two vertices a & b are said to be adjacent if there is an edge connecting a & b. For instance, in given Figure, vertices 5 & 4 are adj

Calculation of time complexity, Example: Assume the following of code: ...

Example: Assume the following of code: x = 4y + 3 z = z + 1 p = 1 As we have been seen, x, y, z and p are all scalar variables & the running time is constant irrespective

Method to add an element in circular queue, Q. Let us consider a queue is h...

Q. Let us consider a queue is housed in an array in circular fashion or trend. It is required to add new items to the queue. Write down a method ENQ to achieve this also check whet

Adjacency matrix representation of a graph, An adjacency matrix representat...

An adjacency matrix representation of a graph cannot having information of : Parallel edges

Design a binary search tree, Binary Search Tree usage: Write a progra...

Binary Search Tree usage: Write a program to compare the time taken for a search in a skewed tree, a balanced tree, and a random tree. Speci cally, your program should do the

Project, human resource management project work in c++

human resource management project work in c++

Explain b tree (binary tree), B Tree Unlike a binary-tree, every node o...

B Tree Unlike a binary-tree, every node of a B-tree may have a variable number of keys and children. The keys are stored in non-decreasing order. Every key has an associated ch

Algorithm that counts number of nodes in a linked list, Q. Write an algorit...

Q. Write an algorithm that counts number of nodes in a linked list.                                       A n s . Algo rithm to Count No. of Nodes in Linked List C

Brute force, Determine the number of character comparisons made by the brut...

Determine the number of character comparisons made by the brute-force algorithm in searching for the pattern GANDHI in the text

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd