4. Let G (V, E) be a directed graph. Suppose we have performed a DFS traversal ofG, and for each vertex v, we know its pre and post numbers. Show the following:(a) If for a pair of vertices u, v € V, pre(u) < pre(v) < post(v) < post(u), then thereis a directed path from u to v in G.(b) If for a pair of vertices u, v € V, pre(u) < post(u) < pre(v) < post(v), then thereis no directed path from u to v in G.

Proofs for a, b is given below :

Answered: = Let G (V, E) be a directed graph.…

Computer Networking: A Top-Down Approach (7th Edition)

7th Edition

ISBN:9780133594140

Author:James Kurose, Keith Ross

Publisher:James Kurose, Keith Ross

Chapter1: Computer Networks And The Internet

Section: Chapter Questions

Problem R1RQ: What is the difference between a host and an end system? List several different types of end...

See similar textbooks

Similar questions

Let G = (V, E) be an undirected graph and each edge e ∈ E is associated with a positive weight ℓ(e).For simplicity we assume weights are distinct. Is the following statement true or false? Let P be the shortest path between two nodes s, t. Now, suppose we replace each edge weight ℓ(e) withℓ(e)^2, then P is still a shortest path between s and t.
Let G be a directed graph having V vertices and E edges. A transitive closure is a matrix M such that MiLj] is true if there is a path from vertex v; to vertex vj, else Mi[j] is false. How will you use DFS to compute the matrix M in O(V2 + VE) time?
let g be the following dierected graph
1. Run DFS-with-timing on this graph G: give the pre and post number of each vertex. Whenever there is a choice of vertices to explore, always pick the one that is alphabetically first. 2. Draw the meta-graph of G. 3. What is the minimum number of edges you must add to G to make it strongly connected (i.e., it consists of a single connected component after adding these edges)? Give such a set of edges. b.
3. 4. Given a directed acyclic graph G = (V, E) and two vertices s, te V, design an efficient algorithm that computes the number of different directed paths from s to t. Define the incidence matrix B of a directed graph with no self-loop to be an nxm matrix with rows indexed by vertices, column indexed by edges such that Bij = -1 1 0 if edge j leaves vertex i, if edge jenters vertex i, otherwise. Let BT be the transpose of matrix B. Find out what the entries of the n x n matrix BBT stand for.
Let G be a graph, where each edge has a weight. A spanning tree is a set of edges that connects all the vertices together, so that there exists a path between any pair of vertices in the graph. A minimum-weight spanning tree is a spanning tree whose sum of edge weights is as small as possible. Last week we saw how Kruskal's Algorithm can be applied to any graph to generate a minimum-weight spanning tree. In this question, you will apply Prim's Algorithm on the graph below. You must start with vertex A. H 4 4 1 3 J 2 C 10 4 8 B 9 F 18 8 There are nine edges in the spanning tree produced by Prim's Algorithm, including AB, BC, and IJ. Determine the exact order in which these nine edges are added to form the minimum-weight spanning tree. 3.
Square graph. The square of a directed graph G = (V,E) is the graph G^2 =(V,E^2)suchthat(u,w)∈E^2 if and only iff or some v∈V both(u,v)∈E and (v, w) ∈ E; that is, there is a path of exactly two edges. (i) Suppose that G is represented by an adjacency list. Describe an efficient algorithm for computing G^2 from G. (ii) Suppose that G is represented by an adjacency matrix. Describe an efficient algorithm for computing G^2 from G.
Given a digraph, find a bitonic shortest path from s to every other vertex (if one exists). A path is bitonic if there is an intermediate vertex v suchthat the edges on the path from s to v are strictly increasing and the edges on the pathfrom v to t are strictly decreasing. The path should be simple (no repeated vertices).
We have a connected graph G=(V,E), and a specific vertex u∈V. Suppose we compute a depth-first search tree rooted at u, and obtain a tree T that includes all nodes of G. Suppose we then compute a breadth-first search tree rooted at u, and obtain the same tree T. Prove that G=T. (In other words, if T is both a depth-first search tree and a breadth-first search tree rooted at u, then G cannot contain any edges that do not belong to T.)
Let G = (V, E) be an undirected graph and each edge e ∈ E is associated with a positive weight ℓ(e).For simplicity we assume weights are distinct. Is the following statement true or false? Let T be a minimum spanning tree for the graph with the original weight. Suppose we replace eachedge weight ℓ(e) with ℓ(e)^2, then T is still a minimum spanning tree.
Consider an undirected graph on 8 vertices, with 12 edges given as shown below: Q2.1 Give the result of running Kruskal's algorithm on this edge sequence (specify the order in which the edges are selected). Q2.2 For the same graph, exhibit a cut that certifies that the edge ry is in the minimum spanning tree. Your answer should be in the form E(S, V/S) for some vertex set S. Specifically, you should find S.
Write to code describes how to create the links dataset that represents the input graph. In this particular case, the links represent a directed network. The links dataset has only the nodes identification, which means, the from and to variables. The link weights in the transitive closure problem are irrelevant. In other words, it doesn’t matter the cost or the weight of the links, the algorithm searches for the possible paths to connect the nodes within the input graph. If there is a link or a set of links, no matter the weights, that connects node i to node j, that is the matter.

SEE MORE QUESTIONS

Recommended textbooks for you

Computer Networking: A Top-Down Approach (7th Edi…

Computer Engineering

ISBN:

9780133594140

Author:

James Kurose, Keith Ross

Publisher:

PEARSON

Computer Organization and Design MIPS Edition, Fi…

Computer Engineering

ISBN:

9780124077263

Author:

David A. Patterson, John L. Hennessy

Publisher:

Elsevier Science

Network+ Guide to Networks (MindTap Course List)

Computer Engineering

ISBN:

9781337569330

Author:

Jill West, Tamara Dean, Jean Andrews

Publisher:

Cengage Learning

Computer Networking: A Top-Down Approach (7th Edi…

Computer Engineering

ISBN:

9780133594140

Author:

James Kurose, Keith Ross

Publisher:

PEARSON

Computer Organization and Design MIPS Edition, Fi…

Computer Engineering

ISBN:

9780124077263

Author:

David A. Patterson, John L. Hennessy

Publisher:

Elsevier Science

Network+ Guide to Networks (MindTap Course List)

Computer Engineering

ISBN:

9781337569330

Author:

Jill West, Tamara Dean, Jean Andrews

Publisher:

Cengage Learning

Concepts of Database Management

Computer Engineering

ISBN:

9781337093422

Author:

Joy L. Starks, Philip J. Pratt, Mary Z. Last

Publisher:

Cengage Learning

Prelude to Programming

Computer Engineering

ISBN:

9780133750423

Author:

VENIT, Stewart

Publisher:

Pearson Education

Sc Business Data Communications and Networking, T…

Computer Engineering

ISBN:

9781119368830

Author:

FITZGERALD

Publisher:

WILEY

SEE MORE TEXTBOOKS