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

Linked list, how to creat atm project by using linked list?

how to creat atm project by using linked list?

Matrix stored in memory, Method to measure address of any element of a matr...

Method to measure address of any element of a matrix stored in memory. Let us consider 2 dimensional array a of size m*n further consider that the lower bound for the row index

Explain arrays, Arrays :- To execute a stack we need a variable called top,...

Arrays :- To execute a stack we need a variable called top, that holds the index of the top element of stack and an array to hold the part of the stack.

Euclidean algorithm, The Euclidean algorithm is an algorithm to decide the ...

The Euclidean algorithm is an algorithm to decide the greatest common divisor of two positive integers. The greatest common divisor of N and M, in short GCD(M,N), is the largest in

Algorithm for inorder traversals, Step-1: For the current node, verify whet...

Step-1: For the current node, verify whether it contain a left child. If it has, then go to step-2 or else go to step-3 Step-2: Repeat step-1 for left child Step-3: Visit (th

The space - time trade off, The Space - Time Trade Off The best algorit...

The Space - Time Trade Off The best algorithm to solve a given problem is one that needs less space in memory and takes less time to complete its implementation. But in practic

Graph with n vertices will absolutely have a parallel edge, A graph with n ...

A graph with n vertices will absolutely have a parallel edge or self loop if the total number of edges is greater than n-1

Define data model, Define data model?  A data model is a collection of ...

Define data model?  A data model is a collection of conceptual tools for explaning data, data relationships, data semantics and consistency constraints.

Representation of arrays?, A representation of an array structure is a mapp...

A representation of an array structure is a mapping of the (abstract) array with elements of type T onto the store which is an array with elements of type BYTE. The array could be

Implementation of stack using linked lists, In the last subsection, we have...

In the last subsection, we have implemented a stack by using an array. While a stack is implemented by using arrays, it suffers from the basic restriction of an array - i.e., its s

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