Name:___________________ Date:_____________ Discrete Quiz Ch.2 1. Which of the following describes a Hamiltonian circuit for the graph below? A) B) C) D) Ans: ABCDEFJIHG ABCDEAFJDIHBGFEJICHGA ABCDEAGHIJFA AEDCBGHIJFA D 2. Which of the following describes a Hamiltonian circuit for the graph below? A) B) C) D) Ans: ABCDEFGA ACBAEGFDEA ACBFGDEA ABCDGEF C 3. On the graph below, which routing is produced by using the nearest-neighbor algorithm to solve the traveling salesman problem? A) B) C) D) Ans: ABCDA ABDCA ACBDA ABCD B 4. For the graph below, what is the cost of the Hamiltonian circuit obtained by using the nearest-neighbor algorithm, starting at A? A) B) C) D) Ans: 60 54 62 66 D 5. Which path listed forms a Hamiltonian circuit on the graph below? A) B) C) D) Ans: ADCBFGHEA ABCDHGFE ABCDHGFEA ABCDHGFEHDA C 6. On a map there are roads from town A of length 10, 26, 12, and 50 miles. Using the nearest-neighbor algorithm for finding a Hamiltonian circuit starting at town A, which road would be traveled first? A) road of length 10 B) road of length 26 C) road of length 12 D) road of length 50 Ans: A 7. For the traveling salesman problem (Hamiltonian circuit) applied to six cities, how many tours are possible? A) 60 B) 120 C) 360 D) 720 Ans: B 8. For the traveling salesman problem (Hamiltonian circuit) applied to five cities, how many unique tours are possible? A) 120 B) 60 C) 24 D) 12 Ans: D 9. For the traveling salesman problem applied to seven cities, how many unique tours are possible? A) 360 B) 720 C) 2520 D) 5040 Ans A 10. A connected graph G has 32 vertices. How many vertices does a spanning tree of G have? A) 30 B) 31 C) 32 D) 33 Ans: C 11. On the graph below, which routing is produced by using the sorted-edges algorithm to solve the traveling salesman problem? A) B) C) D) Ans: ABCDA ABDCA ACBDA ABCD A 12. For the graph below, what is the cost of the Hamiltonian circuit obtained by using the sorted-edges algorithm? A) B) C) D) Ans: 220 225 235 295 C 13. For the graph below, which routing is produced by using the sorted-edges algorithm to solve the traveling salesman problem? A) B) C) D) Ans: ACBEDA ABCEDA ABEDCA ADCEBA A 14. Use Kruskal's algorithm for minimum-cost spanning trees on the graph below. The cost of the tree found is: A) B) C) D) Ans: 5 9 12 15 B 15. Use Kruskal's algorithm for minimum-cost spanning trees on the graph below. The cost of the tree found is: A) B) C) D) Ans: 23 20 16 5 C 16. Use Kruskal's algorithm for minimum-cost spanning trees on the graph below. The cost of the tree found is: A) B) C) D) Ans: 47 25 22 15 C 17. If the order-requirement digraph for a collection of tasks is shown below, then what is the minimum completion time for the collection of tasks? A) B) C) D) Ans: 64 minutes 43 minutes 36 minutes 28 minutes B 18. What is the earliest possible completion time for a job whose order-requirement digraph is shown below? A) B) C) D) Ans: 15 22 34 19 D 19. The nearest-neighbor algorithm for solving the traveling salesman problem always produces the same result as the sorted-edges algorithm. A) True B) False Ans: B 20. When Kruskal's algorithm is used to find a minimum-cost spanning tree on a graph, which of the following is false? A) Circuits are not permitted in the tree. B) The tree contains the edge of the graph of minimum cost. C) The tree is not necessarily connected. D) The tree may contain the edge of the highest cost. Ans: C 21. A spanning tree of a graph must contain every edge of the graph. A) True B) False Ans: B 22. A digraph is a graph with exactly two vertices. A) True B) False Ans: B 23. The graph below shows the cost (in hundreds of dollars) of installing telephone wires between the work spaces in an office complex. Use Kruskal's algorithm for minimumcost spanning trees to find the cost for establishing this phone network. A) B) C) D) Ans: $2100 $2400 $2900 $6200 B 24. Given the two graphs shown below, which one represents a tree? A) B) C) D) Ans: I only II only Both I and II Neither I nor II B 25. Kris has 3 pairs of pants of different colors, 5 shirts of different colors, and 2 pairs of shoes. How many different outfits can Kris create? A) 2 B) 10 C) 30 D) 50 Ans: C