use Time::HiRes qw(gettimeofday tv_interval);
use Test::More;
use perl_calc;
use c_calc;

$start_time_c = [ gettimeofday ];
$c_calc = c_calc::calc_pi();
$end_time_c = [ gettimeofday ];
$elapsed_c = tv_interval($start_time,$end_time);

$start_time_perl = [ gettimeofday ];
$perl_calc = perl_calc::calc_pi();
$end_time_perl = [ gettimeofday ];
$elapsed_perl = tv_interval($start_time,$end_time);

$differences = abs($elapsed_perl - $elapsed_c);

if(ok($c_calc == $perl_calc, "Pi number calc"))
{
	print "C computation time = $elapsed_c\n";
	print "Perl computation time = $elapsed_perl\n";
	print "Differences = $differences\n";
}

done_testing;

##</code><code>##

package c_calc;
use Inline 'C';

1;
__END__

__C__
double my_abs(double num)
{
	return (num > 0)? num : -num;
}

double calc_pi()
{
	double real_pi = 3.14159265358979;
	double my_pi = 0;
	double step_sign = 1;
	unsigned long long i = 1;
	while(my_abs(real_pi - my_pi) > 0.00000001)
	{
		my_pi += 4.0/i * step_sign;
		step_sign *= -1;
		i += 2;
	}
	return my_pi;
}