Implemented Introsort

[Kishan-Ved]

References to other Issues or PRs or Relevant literature

Fixes #545

Brief description of what is fixed or changed

Implemented Introsort.

[codecov]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

Comparison is base (1942891) 97.601% compared to head (13d4dfe) 97.552%.

Additional details and impacted files

@@              Coverage Diff              @@
##              main      #549       +/-   ##
=============================================
- Coverage   97.601%   97.552%   -0.050%     
=============================================
  Files           34        34               
  Lines         4295      4331       +36     
=============================================
+ Hits          4192      4225       +33     
- Misses         103       106        +3     

Files	Coverage Δ
pydatastructs/linear_data_structures/__init__.py	100.000% <ø> (ø)
pydatastructs/linear_data_structures/algorithms.py	99.215% <91.666%> (-0.574%)	⬇️

[czgdp1807]

I think this is because of heapsort's limitation, right? Please mention here about this.

[Kishan-Ved]

Yes, that is because of the current heapsort function's limitation.

[Kishan-Ved]

Should I write that as a comment in the code?

[Kishan-Ved]

Changes made.

[Kishan-Ved]

I've done the mentioned changes: Added comment to code that a custom compactor cannot be taken due to heapsort's limitation.
I've also removed the commented statement of import stack.

[Kishan-Ved]

1 check didn't pass, I believe this is due to some backend issue.

=========================== short test summary info ============================
FAILED pydatastructs/utils/tests/test_code_quality.py::test_backend_argument_message - AssertionError: assert '<function intro_sort at 0x7f97b968adc0>' in 'As of 1.0.1-dev version, only Python backend is supported for <function next_permutation at 0x7f97b968a940> API'
 +  where '<function intro_sort at 0x7f97b968adc0>' = str(<function intro_sort at 0x7f97b968adc0>)
======= 1 failed, 160 passed, 2 xfailed, 7 xpassed in 138.76s (0:02:18) ========

[Kishan-Ved]

All checks pass, the code suggested had next_permutation by mistake, which I changed to my function: intro_sort

[Kishan-Ved]

Thank you for your help! @czgdp1807
This is one of my first prominent open source code contributions! This helped me learn about reading, understanding and managing a large codebase. I'm delighted and eager to contribute more to this organization :)

Also please check the issue I faced, which I've mentioned here: #547 , along with the solution.