Digit factorials: improve performance.
Solve the problem 35 'Circular primes'.
fix a bug in argument check with a empty string
Add a script to make problem directory and problem.md conveniently
Solve the problem 36 'Double-base palindromes'
Double-base palindromes: generalize the generator coroutine.
Solve synapsoft interview question.
.gitignore: ignore temporary files and object files.
synapsoft/minsum: modify usage message.