07-08数据结构试题和答案.doc

浙江大学2007–2008学年秋季学期 《数据结构基础》课程期末考试试卷 开课学院： 软件院、计算机、竺可桢学院 ，考试形式：闭卷，允许带_ 无 入场 考试时间：_2007_年_11_月_17日, 所需时间： 120 分钟 考生姓名： ___学号： 专业： ____教师： 题序 一 二 三 四 总 分 得分 评卷人 Answer Sheet Part I 1. c 2. a 3. d 4. d 5. c 6. b 7. a 8. b 9. b 10. c Part II 1. ( H-Elements[ 1 ] ( Child != H-Size H-Elements[ Child + 1 ] H-Elements[ Child ] ( H-Elements[ i ] = H-Elements[ Child ] 2. ( j = Increment ( Tmp A[ j - Increment ] 3. ( ThisSum + A[j] ( ThisSum = 0 Part III 1. (a) ABEDHIFCGJ (b)ABDEHFICGJ 1. (c) 2. (a) 2. (b) or 3. { 2, –4, 2, 2, -5, 5, 6, 9, 5 } 4. (a) Build max heap and call DeletMax for k times. O(N+k logN) Keep a min heap of k elements. Compare a new element with the root and, DeletMin and Insert the new element if the new one is larger. O(N logk) Sort and take the kth largest. O(N logN) Take a pivot and partition the set as in Quicksort. If k=|S2| then the element must be in S2, recursively find it from S2. If k=|S2|+1, then return the pivot. If k|S2|, then it’s in S1 and it’s the (|S1|-N+k)-th largest element. Recursively find it from S1. Average = O(N). Worst=O(N2). 4. (b) Part IV void Dijkstra( Table T ) {/* T[ ].Count is initialized to be 0. T[start].Count = T[start].balloon */ vertex v, w; for ( ; ; ) { v = smallest unknown distance vertex; if ( v == NotAVertex ) break; T[v].Known = True; for ( each w adjacent to v ) if( !T[w].Known ) if( T[v].Dist + Cvw T[w].Dist ) { Decrease( T[w].Dist to T[v]+Cvw ) T[w].Path = v; T[w].Count = T[v].Count + T[w].balloon; } else if( ( T[v].Dist + Cvw == T[w].Dist ) ( T[v].Count + T[w].balloon T[w].Count ) ) { T[w].Count = T[v].Count + T[w].balloon; T[w].Path = v; /* DO NOT forget this */ } } } NOTE: Please write your answers on the answer sh