solution about xsim

[muzimuzhi]

Why doesn't xsim output the answers in the order of the questions?

You need \printallsolutions, rather than \printsolutions. See package manual, sec. 11. "Printing Solutions" for more info.

\part{solution}
\verb|\printsolutions| prints the solutions of all used exercises of all types \emph{ordered by type}.
\printsolutions[chapter=1,section=1,headings-template=none]
\printsolutions[chapter=1,section=2,headings-template=none]

\verb|\printallsolutions| prints the solutions of all used exercises of all types \emph{ordered by appearance} in the document.
\printallsolutions[chapter=1,section=1,headings-template=none]
\printallsolutions[chapter=1,section=2,headings-template=none]

[muzimuzhi]

Please always wrap multi-line code, here the latex example in (github flavored) markdown code block.

Also, please put some more effort in minimizing your example, for example drop unused packages and see if the problem reproduces with one of the stand document classes.

[Jerrymouse999]

thank you

[Jerrymouse999]

thank you