Merge pull request #1 from julycoding/master

merge master to my own repo
Merge pull request #39 from Boshen/master

improve readability of chapter 4, 5 and 11 (eng version)
增加Java & Python示例（已添加的示例代码全部经过测试），后面3种示例稍后补充。
Merge pull request #2 from julycoding/master

Merge master code to my own repo
Merge pull request #40 from BrickXu/master

第一章1,2节示例代码添加Python语言&Java语言例子
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Merge pull request #42 from lidashuang/patch-3

Update 25.0.md
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Merge pull request #43 from lidashuang/patch-4

Update 25.0.md
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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