anitasv 3.8s vs 3m 19s : Improved using custom hashmap.

[anitasv]

Check List:

• [x] You have run ./mvnw verify and the project builds successfully
• [x] Tests pass (./test.sh <username> shows no differences between expected and actual outputs)
• [x] All formatting changes by the build are committed
• [x] Your launch script is named calculate_average_<username>.sh (make sure to match casing of your GH user name) and is executable
• [x] Output matches that of calculate_average_baseline.sh
• [x] For new entries, or after substantial changes: When implementing custom hash structures, please point to where you deal with hash collisions (line number)

Hash Collision Handling: Line 128 to 153.

• Execution time: 3.8 seconds
• Execution time of reference implementation: 3minutes 19 seconds

Improvements: I added the custom hashtable back.

[anitasv]

@gunnarmorling If it is not performing better than older 00:08.752 then don't bother merging this change. Old one is much cleaner.

[gunnarmorling]

00:07.712 now, nice.