41 lines
674 B
Perl
41 lines
674 B
Perl
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#!/usr/bin/env perl
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# prime number calculation
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# author: david@socialnerds.org
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my $num = 3;
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print "highest prime number: ";
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chomp(my $maxnum = <STDIN>);
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my $count = 2;
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print "2\n3\n";
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while ( $num <= $maxnum )
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{
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$i=3;
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while ( $i <= int($num**(1/2)+1) )
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{
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if ( $i != 1 && $i < $num && $i%2 != 0 )
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{
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if ( $num % $i != 0 ) {
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$probably = "true"
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} else {
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$probably = "false";
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last;
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}
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}
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$i += 2;
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}
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if ( $probably eq "true" )
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{
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print "$num\n";
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$count++;
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}
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$num += 2;
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}
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print "prime number count: $count\n";
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