The OP does not use grep and hashes to calculate prime numbers. It uses a subroutine called is_prime(), which is not included in the posted code.

Could you post your version, so we can learn from it?

The way forward always starts with a minimal test.

In reply to Re^2: Unable to Understand grep and hash use for prime no. by 1nickt
in thread Unable to Understand grep and hash use for prime no. by shankonit

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