For all weekly assignments and video thinking questions for answers and analysis, see Zhejiang University Data Structure Thinking Questions + Weekly Practice Answers
Topic 1: In heap sorting, element subscripts start from 0. Then for the element with subscript i, the subscripts of the left and right children are:
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A. 2i-1, 2i
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B. 2i, 2i + 1
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C. 2i + 1, 2i + 2
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D. 2i + 2, 2i + 3
Choose C
0's left child 1 right child 2, substitute in, only C pairs.
Topic 2: Heap sorting of N records. In the worst case, the time complexity is
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A.
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B.
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C.
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D.
What does this question mean? I didn't see anything to think about, shouldn't it be the NlogN introduced in the course? Choose C.
Topic three: There is a set of records (46,77,55,38,41,85), the initial heap established by heap sort is
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A. 38,77,55,46,41,85
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B. 38,41,46,77,55,85
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C. 85,55,77,38,41,46
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D. 85,77,55,38,41,46
Just build the largest heap:
Choose D
Topic 4: Heap sort is stable.
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A. √
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B. ×
error. A rough idea is unstable: when the minimum heap is established and when it is sorted, the order is disordered.
To be more precise, let's take an example: suppose the minimum heap created is as follows:
