feat: add rust solutions for lc No.2839,2840

[yanglbme]

No description provided.

[Copilot]

Pull request overview

Adds Rust implementations for LeetCode 2839 and 2840 and refactors existing solutions/snippets to use simpler equality checks.

Changes:

• Added Rust solutions for LC 2839 and 2840.
• Simplified TypeScript solutions by replacing manual loops with every(...) checks.
• Updated Python solutions and READMEs to use Counter(...)-based comparisons.

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
solution/2800-2899/2840.Check if Strings Can be Made Equal With Operations II/Solution.ts	Refactors validation to cnt.every(...) for concise zero-checking
solution/2800-2899/2840.Check if Strings Can be Made Equal With Operations II/Solution.rs	Adds Rust solution using parity buckets and frequency deltas
solution/2800-2899/2840.Check if Strings Can be Made Equal With Operations II/Solution.py	Switches to Counter comparisons for parity slices
solution/2800-2899/2840.Check if Strings Can be Made Equal With Operations II/Solution.java	Formatting-only adjustment at file end
solution/2800-2899/2840.Check if Strings Can be Made Equal With Operations II/README_EN.md	Updates snippets (Python uses Counter, TS simplified) and adds Rust snippet
solution/2800-2899/2840.Check if Strings Can be Made Equal With Operations II/README.md	Same as above for non-English README
solution/2800-2899/2839.Check if Strings Can be Made Equal With Operations I/Solution.ts	Refactors validation to cnt.every(...) for concise zero-checking
solution/2800-2899/2839.Check if Strings Can be Made Equal With Operations I/Solution.rs	Adds Rust solution using parity buckets and frequency deltas
solution/2800-2899/2839.Check if Strings Can be Made Equal With Operations I/Solution.py	Switches to Counter comparisons for parity slices
solution/2800-2899/2839.Check if Strings Can be Made Equal With Operations I/README_EN.md	Updates snippets (Python uses Counter, TS simplified) and adds Rust snippet
solution/2800-2899/2839.Check if Strings Can be Made Equal With Operations I/README.md	Same as above for non-English README

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[Copilot]

Counter is used but not imported in this file, which will raise a NameError at runtime. Add from collections import Counter at the top (or qualify the reference appropriately) so the solution runs.

[Copilot]

Counter is used but not imported in this file, which will raise a NameError at runtime. Add from collections import Counter at the top (or qualify the reference appropriately) so the solution runs.

[Copilot]

The README Python snippet now uses Counter but doesn’t show the required import (from collections import Counter). Update the snippet to include the import so readers can run it as-is.

Suggested change

	```python
	```python
	from collections import Counter

[Copilot]

The README Python snippet now uses Counter but doesn’t show the required import (from collections import Counter). Update the snippet to include the import so readers can run it as-is.

Suggested change

	```python
	```python
	from collections import Counter

[Copilot]

The README Python snippet now uses Counter but doesn’t show the required import (from collections import Counter). Update the snippet to include the import so readers can run it as-is.

Suggested change

	```python
	```python
	from collections import Counter

[Copilot]

The README Python snippet now uses Counter but doesn’t show the required import (from collections import Counter). Update the snippet to include the import so readers can run it as-is.

Suggested change

	```python
	```python
	from collections import Counter