Skip Lists Complete the Editor orTrees es p partn tner e - - PowerPoint PPT Presentation

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Oct 24, 2022 429 likes •545 views

Skip Lists Complete the Editor orTrees es p partn tner e evaluati ation on by Wednesday night An alternative to balanced trees Sorted data. Random. Expected times are O(log n). 1-2 Indexed lists. One-level index.

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Skip Lists

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 Complete the Editor

rTrees

es p partn tner e evaluati ation

n by

Wednesday night

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An alternative to balanced trees Sorted data. Random. Expected times are O(log n).

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 Indexed lists.

One-level index.
2nd-level index.
3rd-level index
log-n-level index.

 Problem: insertion and deletion.  Solution: Randomized node height: Skip lists.

Pugh, 1990 CACM.

 http://iamwww.unibe.ch/~wenger/DA/SkipList/

1-2

Notice that skip lists do not share with binary trees the problem that threads are designed to solve. Remember the problem with keeping trees completely balanced”?

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 Uses a bit more space, makes the code

simpler.

 Michael Goodrich and Roberto Tamassia.

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 No guarantees that we won't get O(N)

behavior.

The interaction of the random number generator

and the order in which things are inserted/deleted could lead to a long chain of nodes with the same height.

But this is very unlikely.
Expec