中原大學九十三學年度博士班入學招生考試
93年6月9日 8:30~10:00 電子工程學系資訊組  誠實是我們珍視的美德,
我們喜愛「拒絕作弊,堅守正直」的你!
科目:演算法  
可使用計算機,惟僅限不具可程式及多重記憶者 □不可使用計算機
 
Note: Show your work and write the answer clearly.
   
1. Give asymptotically tight bound for each of the following recurrences. (15%)
  (a)
  (b)
  (c)
     
2. Let and be constants, and let f(n) be a nonnegative function defined on exact powers of b. A function g(n) is defined over exact powers of b by: (10%)
 
  (a) Suppose the function f(n) is bounded asymptotically as: , give the asymptotically tight bound for the function g(n) in
  (b) Following the problem 2(a), if a function T(n) is defined as: , then give the asymptotically tight bound for the function T(n) in
     
3. Huffman code is an effective technique for compressing data. If we use the Huffman codes to compress a data file containing only six characters, i.e., {a, b, c, d, e, f}, where the probabilities of the characters are 0.45, 0.13, 0.12, 0.16, 0.09, and 0.05, respectively. (10%)
  (a) Construct a binary tree corresponding to the optimal Huffman codes.
  (b) If the character c and f are encoded as 100 and 1100, what are the characters d and e encoded?
     
4. Given the following graph,
 
  (a) Determine the total number of spanning trees. (7%)
  (b) Simply describe an algorithm for finding the minimum spanning tree and use the algorithm to find the minimum spanning tree of the given graph. (10%)
     
5. Let denote the number of different binary trees with n nodes, which can be defined as follows:
 
  and . Determine the number of different binary trees with 4 nodes. (10%)
     
6. For the following three data points , namely (0, 0), (1, 1), (2, 3), the Lagrange's formula for data interpolation is defined as:
 
  Calculate A(0.5) and A(1.5). (10%)
     
7. For each of the following statements, determine True or False: (16%)
  (a) The algorithm for finding the longest common subsequence (LCS) is an example of a dynamic programming algorithm.
  (b) Quicksort is an unstable sorting algorithm, while Heapsort is a stable sorting algorithm.
  (c) The problem of determining if a graph G has an Euler tour is an NP-complete problem.
  (d) The algorithm for the fast Fourier transform (FFT) is an example of a divide-and-conquer algorithm.
  (e) The Bellman-Ford algorithm can be used to find the single-source shortest paths of a graph, even if the graph has negative weights.
  (f) To show that the clique problem is NP-complete, one must show that the vertex-cover problem reduces to the clique problem.
  (g) The tower of Hanoi problem is a P problem which is solvable in polynomial time.
  (h) The 3-coloring problem is an NP-complete problem.
     
8. For the directed graph specified below: (12%)
     G = (V, E),
     V(G) = {a, b, c, d},
     E(G) = {(a, b), (a, c), (b, d), (c, d), (b, a), (d, c)}.
  (a) Find the adjacency matrix.
  (b) Determine the graph , the transpose of the graph G.
  (c) Find the transitive closure.
     
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