Question 2. Use the greedy algorithm to color the graph below, ordering the vertices alphabetically. Is this coloring optimal? How do you know? Question 2. Use the greedy algorithm to color...
a) Prove that by correctly numbering the vertices of your graph, the greedy colouring algorithm will give you an optimal coloring. (Hint: start with an optimal coloring of G, and use it to number your vertices.) b) Does this coloring algorithm always yield an optimal result? c) What can happens when you apply this algorithm to a complete bipartite graph Knn.
3.3. Run the DFS-based topological ordering algorithm on the following graph. Whenever you have a choice of vertices to explore, always pick the one that is alphabetically first. (a) Indicate the pre and post numbers of the nodes. (b) What are the sources and sinks of the graph? (c) What topological ordering is found by the algorithm? (d) How many topological orderings does this graph have?
3.3. Run the DFS-based topological ordering algorithm on the following graph. Whenever you have...
Please write a python function for :
greedy: This function takes two inputs: one a graph, and the other an ordering of the vertices as a list, and returns the proper vertex-coloring produced by the greedy algorithm over the ordering in the list. Examples: greedy({"A" : ["B", "C"], "B" : ["A"], "C" : ["A"]},[“A”, “B”, “C”]) should return {“A” : 1, “B” : 2, "C" : 2} greedy({“A” : ["B"], "B" : [“A”, “C”],"C" : [“B”, “D”), “D" : ["C"]},[“A”,...
Give an example of a graph G with at least 10
vertices such that the greedy 2-approximation algorithm for
Vertex-Cover given below is guaranteed to produce a suboptimal
vertex cover.
Algorithm Vertex CoverApprox(G): Input: A graph G Output: A small vertex cover C for G while G still has edges do select an edge e (v, w) of G add vertices v and w to C for each edge f incident to v or w do remove f from G...
A 2-coloring of an undirected graph with n vertices and m edges is the assignment of one of two colors (say, red or green) to each vertex of the graph, so that no two adjacent nodes have the same color. So, if there is an edge (u,v) in the graph, either node u is red and v is green or vice versa. Give an O(n + m) time algorithm (pseudocode!) to 2-colour a graph or determine that no such coloring...
Dijkstra's Algorithm
Using the following graph, please answer each question below.
Dijkstra's Algorithm 5) Consider the following graph: 80 70 90 60 10 Use Dijkstra's algorithm to find the costs of the shortest paths from A to each of the other vertices. Show your work at every step. a. b. Are any of the costs you computed using Dijkstra's algorithm in part (a) incorrect? Why or whynot? Explain how you can use Dijkstra's algorithm the recover the actual paths...
Graph Question
D Question 1 2 pts Which Graph Algorithm (as described in lecture) relies on a Priority Queue to give it maximum efficiency? Prim's Algorithm ⓔ Dijkstra's Algorithm Kuemmel-Deppeler Algorithm Topological Ordering Algorithm Kruskal's Algorithm D Question 7 2 pts At the beginning of the Dijkstra's Algorithm, which of the following must be done? Select all correct choices. set all total weights to O mark all vertices as unvisited O sort all edges set all predecessors to null
D...
Algorithm Question
5. Below is a graph with edge lengths. Apply Dijkstra's algorithm to find the shortest paths, starting at vertex A, to all other vertices. Write down the sequence in which the edges are chosen, breaking ties by using vertices at the same length in alphabetic orde. 3 Ga 2
5. Below is a graph with edge lengths. Apply Dijkstra's algorithm to find the shortest paths, starting at vertex A, to all other vertices. Write down the sequence in...
Question 6 Let G be the weighted graph (a) Use Dijkstra's algorithm to find the shortest path from A to F. You can do all the work on a single diagram, but, to show that you have used the algorithm correctly, if an annotation needs updating do not erase itjust put a line through it and write the new annotation above that b) In what order are the vertices added to the tree? (c) Notice that the algorithm does not,...
Show all work for full credit. PART A Graph Theorv). 01.a. Model the following problem into a graph coloring problem A local zoo wants to take visitors on animal feeding tours, and is considering the following tours: Tour 1 visits the monkeys, birds, and deer Tour 2 visits the elephants, deer and giraffes; Tour 3 visits the birds, reptiles and bears Tour 4 visits the kangaroos, monkeys and bears Tour 5 visits birds, kangaroos and pandas; Monday, Wednesday and Friday...