namespace;
include rt, run;

// o3 calls between functions: arguments in registers, results on the stack, and the ways a call can leave the fast path
fn put_f(x) { asm { x @ #1220 } return 0; }
struct node { int v; node *next; };
o3 int fib(int n) { if (n < 2) return n; return fib(n - 1) + fib(n - 2); }
o3 int ev(int n);
o3 int od(int n) { if (n == 0) return 0; return ev(n - 1); }
o3 int ev(int n) { if (n == 0) return 1; return od(n - 1); }
o3 int three(int a, int b, int c) { return a * 100 + b * 10 + c; }
o3 int four(int a, int b, int c, int d) { return three(a, b, c) * 10 + d; }
o3 int zero() { return 7; }
o3 int ack(int m, int n) { if (m == 0) return n + 1; if (n == 0) return ack(m - 1, 1); return ack(m - 1, ack(m, n - 1)); }
o3 float half(float x, int k) { if (k == 0) return x; return half(x / 2.0, k - 1); }
o3 int noisy(int n) { if (n == 0) return 0; rt.put_n(n); rt.put_c(' '); return n + noisy(n - 1); }
unchecked o3 int sumlist(node *p) { int s = 0; while (p) { s = s + p.v; p = p.next; } return s; }
unchecked o3 int build(int n) {
	node *h = 0;
	for (int i = 1; i <= n; i++) { node *x = rt.new(node); x.v = i; x.next = h; h = x; }
	int s = sumlist(h);
	while (h) { node *t = h.next; rt.free(h); h = t; }
	return s;
}
unchecked o3 int mix(int a, int b) { return three(a, zero(), b) + fib(a) + four(1, 2, 3, b); }
unchecked fn main() {
	rt.put_n(fib(20)); rt.put_c(' ');
	rt.put_n(ev(10)); rt.put_c(' '); rt.put_n(ev(7)); rt.put_c(' ');
	rt.put_n(three(1, 2, 3)); rt.put_c(' '); rt.put_n(four(4, 5, 6, 7)); rt.put_c(' '); rt.put_n(zero()); rt.put_c(' ');
	rt.put_n(ack(2, 3)); rt.put_c(' ');
	put_f(half(64.0, 3)); rt.put_c(' ');
	rt.put_n(build(100)); rt.put_c(' ');
	rt.put_n(mix(6, 9)); rt.put_c(10);
	rt.put_n(noisy(4)); rt.put_c(10);
	return 0;
}