Reduced Time Complexity

[abhijitgawai]

Describe your change:

1st :-
Added Base Condition to Reduce Time Complexity

2nd :-
Previously Time Complexity was O( max( len(first_str) , len(second_str) ) )
So, now on line 26, I am considering minimum length of both string.
Select alternate characters of both strings. For max( len(first_str) , len(second_str) ) times and exit for loop
Then Concatenate remaining characters of larger string. <- This does not require for loop, Thus reducing Time Complexity.

Now Time Complexity is O( min ( len(first_str) , len(second_str) ) )

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Documentation change?

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new Python files are placed inside an existing directory.
• All filenames are in all lowercase characters with no spaces or dashes.
• All functions and variable names follow Python naming conventions.
• All function parameters and return values are annotated with Python type hints.
• All functions have doctests that pass the automated testing.
• All new algorithms have a URL in its comments that points to Wikipedia or other similar explanation.
• If this pull request resolves one or more open issues then the commit message contains Fixes: #{$ISSUE_NO}.

[cclauss]

Suggested change

	if len(first_str)==0:
	return second_str
	if len(second_str)==0:
	return first_str
	if not first_str or not second_str:
	return first_str and second_str