// shared cons cells, a shared string, and a cycle. the collector reclaims
// them once nothing points at them. free of a shared cell does nothing.
fn main() {
	let base = live_objects(), a, b, c, s, p, q, cyc, n, tri;
	a = cons(1, 2);
	b = cons(a, 3);
	c = cons(a, 4);
	put_n(car(a)); put_c(32);
	put_n(cdr(a)); put_c(32);
	put_n(car(car(b))); put_c(32);
	put_n(cdr(c)); put_c(32);
	put_n(car(b) == a); put_c(32);
	put_n(is_shared(a)); put_c(32);
	n = live_objects();
	free(a);
	put_n(live_objects() == n); put_c(32);
	put_n(car(a)); put_c(32);
	s = n_to_s(42);
	p = cons(s, 0);
	q = cons(s, 1);
	put_n(s_to_n(car(p))); put_c(32);
	put_n(car(p) == car(q)); put_c(32);
	cyc = cons(0, 1);
	cyc[0] = cyc;
	put_n(cdr(cyc)); put_c(32);
	put_n(car(cyc) == cyc); put_c(32);
	tri = triple(5, 6, 7);
	put_n(tget(tri, 1)); put_c(32);
	a = 0; b = 0; c = 0; s = 0; p = 0; q = 0; cyc = 0; tri = 0;
	scrub();
	gc();
	put_n(live_objects() - base); put_c(10);
	return 0;
}