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Merge pull request #42 from lidashuang/patch-3

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Merge pull request #43 from lidashuang/patch-4

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add a new TopK aDynamic data collection
Merge pull request #44 from xtlx2000/a_new_TopK

pull request:add a new TopK algorithm in dynamic data collection
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Merge pull request #4 from julycoding/master

Merge master code to my own repo