测试3

    A[Hard edge] -->|Link text| B(Round edge)
    B --> C{Decision}
    C -->|One| D[Result one]
    C -->|Two| E[Result two]

    Alice->John: Hello John, how are you?
    loop every minute
        John-->Alice: Great!
    end

Alice->Bob: Hello Bob, how are you?
Note right of Bob: Bob thinks
Bob-->Alice: I am good thanks!

st=>start: Start:>https://www.zybuluo.com
io=>inputoutput: verification
op=>operation: Your Operation
cond=>condition: Yes or No?
sub=>subroutine: Your Subroutine
e=>end

st->io->op->cond
cond(yes)->e
cond(no)->sub->io

graph TD client1-->|read / write|SVN((SVN server)) client2-->|read only|SVN client3-->|read / write|SVN client4-->|read only|SVN client5(...)-->SVN SVN---|store the data|sharedrive

(sqrt{x^{2}})

[sum_{i=1}^n a_i=0 ]

[f(x_1,x_x,ldots,x_n) = x_1^2 + x_2^2 + cdots + x_n^2 ]

[sum^{j-1}_{k=0}{widehat{gamma}_{kj} z_k} ]