Why not just use something like this:

#!/usr/bin/perl -wl

sub logb10 {
  return log(+shift)/log(10);
}

print int(logb10(100) + logb10(100) + 1);
print int(logb10(321) + logb10(311) + 1);
print int(logb10(321) + logb10(312) + 1);
__DATA__
output:
5
5
6

[download]

Or maybe we could just pull out the magic length method and stop trying to focus on a problem that isn't really a problem?

In reply to Re: Re: Re: Finding Primes by Anonymous Monk
in thread Finding Primes by Tommy

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