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

Explain about the preconditions assertion, Preconditions assertion A ...

Preconditions assertion A precondition is an assertion which should be true at the initiation of an operation. For instance, a square root operation can't accept a negative a

Define graph, A graph is a mathematical structure giving of a set of vertex...

A graph is a mathematical structure giving of a set of vertexes (v1, v2, v3) and a group of edges (e1, e2, e3). An edge is a set of vertexes. The two vertexes are named the edge en

R. Studio, I need a person who has a good background in using R. Studio? I...

I need a person who has a good background in using R. Studio? In adition, a person who is good in using algorithms.

Differentiate between nonpersistent and 1-persistent, Differentiate between...

Differentiate between Nonpersistent and 1-persistent Nonpersistent: If the medium is idle, transmit; if the medium is busy, wait an amount of time drawn from a probability dist

Explain binary search tree, Binary search tree. A binary search tree is...

Binary search tree. A binary search tree is a binary tree that is either empty or in which every node having a key that satisfies the following conditions: - All keys (if an

Define approximating smooth surfaces with polygon nets, Approximating smoot...

Approximating smooth surfaces with Polygon nets Networks of polygons are used to represent smooth surfaces. They are, of course, only an approximation to the true surface, but

Multiple stacks, how multiple stacks can be implemented using one dimension...

how multiple stacks can be implemented using one dimensional array

Define threaded binary tree, Threaded Binary Tree:- By changing the NUL...

Threaded Binary Tree:- By changing the NULL lines in a binary tree to special links known as threads, it is possible to perform traversal, insertion and deletion without using

Sorting algorithms, Sorting is significant application activity. Several so...

Sorting is significant application activity. Several sorting algorithms are obtainable. But, each is efficient for a specific situation or a specific kind of data. The choice of a

What is binary search, What is binary search?   Binary search is most ...

What is binary search?   Binary search is most useful when list is sorted. In binary search, element present in middle of the list is determined. If key (the number to search)

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