style/format-code: reduce code nesting

[Tellcts]

Description

1. Reduced the multiple layers of nesting in match, making the code appear flatter;
2. Remove the explicit import of Deref and fully leverage the compiler's implicit dereferencing behavior;
3. Optimize code logic.

Type of change

• Optimization of code structure

Checklist:

• I ran bellow commands using the latest version of rust nightly.
• I ran cargo clippy --all -- -D warnings just before my last commit and fixed any issue that was found.
• I ran cargo fmt just before my last commit.
• I ran cargo test just before my last commit and all tests passed.
• I added my algorithm to the corresponding mod.rs file within its own folder, and in any parent folder(s).
• I added my algorithm to DIRECTORY.md with the correct link.
• I checked COUNTRIBUTING.md and my code follows its guidelines.

Please make sure that if there is a test that takes too long to run ( > 300ms), you #[ignore] that or
try to optimize your code or make the test easier to run. We have this rule because we have hundreds of
tests to run; If each one of them took 300ms, we would have to wait for a long time.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.83%. Comparing base (7789289) to head (e1260e5).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1043   +/-   ##
=======================================
  Coverage   95.82%   95.83%           
=======================================
  Files         393      393           
  Lines       29971    29977    +6     
=======================================
+ Hits        28721    28729    +8     
+ Misses       1250     1248    -2     

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[Tellcts]

I have review my codes and impove the test coverage.