Prime Finder

primegen.pl

#!/usr/bin/perl
#this program generates $c prime numbers starting from the number 2

use Strict;
use warnings;
use POSIX;
sub genPrimes($$){
	my($ct,$advanced) = @_;
	my ($i,$possPrime,@primes,$j);
	$ct = 1 unless $ct;
	$possPrime =3; 
	@primes = (2);
	while (@primes<$ct) {
		$j=0;
		$div=0;
		if ($advanced) {
			while(!$div && $j<@primes && $primes[$j]<($possPrime/2) ){
				if ($possPrime % $primes[$j] == 0){
					$div=1;
				}
				$j++;
			}
		} else {
			while(!$div && $j<@primes){
				if ($possPrime % $primes[$j] == 0){
					$div=1;
				}
				$j++;
			}
		}
		$primes[@primes]=$possPrime unless $div;
		$possPrime+=2;
		if (@primes % 100 == 0){
			#print $#primes . "\n";
		}
	}
	return @primes;
}

sub convertTime($){
	local($time) = @_;
	print $time;
	$seconds = $time;
	$minutes = floor($time / 60);
	$hours = floor($minutes / 60);
	$seconds -= $minutes * 60;
	$minutes -= $hours * 60;
	return ($hours, $minutes, $seconds);
}

$ct = $ARGV[0];
$start = time();
@primes = genPrimes($ct,0);
$end = time();

foreach(@primes){
	print;
	print "\t";
}
print "\n";

$start = 
$end = 


@startTime = convertTime($start);
@endTime = convertTime($end);
@diffTime = convertTime($end - $start);


print "Start Time: " . $startTime[0] . ":" . $startTime[1] . ":" . $startTime[2] . "\n";
print "End Time: " . $endTime[0] . ":" . $endTime[1] . ":" . $endTime[2] . "\n";
print "Diff Time: " . $diffTime[0] . ":" . $diffTime[1] . ":" . $diffTime[2] . "\n";