eisenstein's code is genius, to say the least. I found a different way of the sieve method, and am wondering which is more efficient.
Thanks!
! usr/bin/perl -w
use strict;
sub prime{
my (@primes,%n);
my $n=shift;
foreach my $r(2..$n){
$n{$r}=1;
}
foreach my $x(2..int(sqrt($n))){
if($n{$x}){
my $a=2*$x;
while ($a <= $n){
$n{$a}=undef;
$a=$a+$x;
}
}
}
foreach my $x(2..$n){
if($n{$x}){
push( @primes, $x);
}
}
return @primes;
}
#find to 100
print join ',',prime(100);
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