#include <u.h>
#include <libc.h>
#include <thread.h>

#define Scale	(100000000000ull)

/*
 * waste time
 */
vlong
πjj(uint j)
{
	vlong v;

	v = 4*Scale / (2*j + 1);
	if(j&1)
		return -v;
	return v;
}

vlong
π(void)
{
	uint i;
	vlong v;

	v = 0;
	for(i = 0; i < 500000000; i++)
		v += πjj(i);
	return v;
}

void
p(void *v)
{
	int i;

	i = (int)v;
	print("%d: %lld\n", i, π());
	threadexits("");
}

void
usage(void)
{
	fprint(2, "usage: burncycles nthread\n");
	threadexits("usage");
}

void
threadmain(int argc, char **argv)
{
	int n, i;

	ARGBEGIN{
	default:
		usage();
	}ARGEND
	n = 0;
	if(argc == 0)
		n = 1;
	else if(argc != 1 || (n = atoi(argv[0])) <= 0)
		usage();
	for(i = 0; i < n-1; i++)
		proccreate(p, (void*)i, 4096);
	p((void*)i);
}