WestMidlands| SDC NOV 2025 | Sara Tahir | Sprint 2 |Improve with precomputing

[SaraTahir28]

Learners, PR Template

Self checklist

• I have titled my PR with Region | Cohort | FirstName LastName | Sprint | Assignment Title
• My changes meet the requirements of the task
• I have tested my changes
• My changes follow the style guide

Changelist

Common prefixes
In the original implementation we compared every pair of strings, which is O(n²). By sorting the list first, strings with similar prefixes become adjacent, so we only need to compare neighbouring pairs. This reduces the complexity to O(n log n)

Count Letters
I have Precomputed lowercase and uppercase character sets to avoid repeated full‑string scans.
This reduces count_letters from O(n²) to O(n).

Questions

I have no Questions. Thankyou.

[cjyuan]

Can you use complexity to explain why your implementations are better than the originals?

[cjyuan]

The indentation and spacing of the code in this file is a bit off. Can you improve the formatting of the code?

[SaraTahir28]

Thankyou for you suggestion, I have addressed this in a seperate commit.

[SaraTahir28]

Can you use complexity to explain why your implementations are better than the originals?

In the original implementation we compared every pair of strings, which is O(n²). By sorting the list first, strings with similar prefixes become adjacent, so we only need to compare neighbouring pairs. This reduces the complexity to O(n log n)

Count Letters
I have Precomputed lowercase and uppercase character sets to avoid repeated full‑string scans.
This reduces count_letters from O(n²) to O(n).

[cjyuan]

Changes and analysis are good! Well done.