Add type hints and default args for problem 20 (#2962)

- Improved variable names
- Added type hints
- Added default argument values for validate_solutions script

Dhruv committed 5y ago

11a5afd8a10b21dfebddcf3c6022402ac463b634

Parent: e41d041

Committed by GitHub <noreply@github.com> on 10/7/2020, 9:59:55 AM