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Re: Perl vs. Python for prime numbers

by choroba (Chancellor)
on Jun 13, 2013 at 21:35 UTC ( #1038845=note: print w/replies, xml ) Need Help??


in reply to Perl vs. Python for prime numbers

I was able to transfer the logic using a block with last:
#!/usr/bin/perl use warnings; use strict; use feature qw(say); for my $n (2 .. 99) { PRIME: { for my $x (2 .. $n - 1) { last PRIME if 0 == $n % $x; } say $n, ' is a primer number'; } }

Update.
But I would rather use something like the following:

for my $n (2 .. 99) { my $is_prime = 1; $is_prime &&= $n % $_ or last for 2 .. sqrt $n; say $n, ' is a primer number' if $is_prime; }

Update 2: &&= used instead of *= to avoid large numbers.

لսႽ ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

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Re^2: Perl vs. Python for prime numbers
by LanX (Chancellor) on Jun 14, 2013 at 07:49 UTC
    > $is_prime &&= $n % $_ or last for 2 .. sqrt $n;

    why so complicated, isn't a simple flag sufficient?

    #!/usr/bin/perl use warnings; use strict; use feature qw(say); for my $n (2 .. 99) { my $prime = 1; for (2 .. $n-1) { $prime = 0, last unless $n % $_; } say $n, ' is a primer number' if $prime; }

    Cheers Rolf

    ( addicted to the Perl Programming Language)

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[james28909]: Good morning!
[james28909]: I have a problem I am trying to solve. I am packaging scripts using pdk and would like the verify the executable name each time it is executed
[Corion]: Hi James!
[james28909]: I looked through the docs, and see that PerlApp::exe() is suppose to return this information but whenever i try to use this, i get the error "Undefined subroutine &PerlApp::exe called"
[james28909]: i just want to verify the integrity of the executables name each time it is run.
[Corion]: Weird. this documentation says what you say.
[Corion]: I assume you are experiencing this with your packaged program. Maybe also include PerlApp.pm in the packaging list?
[james28909]: has anyone else run into this problem? i have tried searching but have not returned many results
[james28909]: ah, good idea.
[Corion]: What does print $PerlApp::VERSION output?

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