Update Readme.md
Add chapter 39~40
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Add chapters 39~40
Update 39.0~40.0.md
add book.json. fix generate error
Merge pull request #184 from marchtea/master

add book.json. fix generate error
Update Readme.md
Update Readme.md
update
Update Readme.md
Update Readme.md
update
update
modify cycle_leader
modify cycle_leader
c++ for cycle_leader