/* fibonacci */

/* F_0 = 0 */
/* F_1 = 1 */
/* F_n = F_{n-1} + F_{n-2} */

struct f0 f1 f2 f3 f4 f5 f6 f7 f8 f9 end;

method fib(x)
	if x < 0 then return -1; end;	f0 :=  0;
	if x < 1 then return f0; end;	f1 :=  1;
	if x < 2 then return f1; end;	f2 :=  1;
	if x < 3 then return f2; end;	f3 :=  2;
	if x < 4 then return f3; end;	f4 :=  3;
	if x < 5 then return f4; end;	f5 :=  5;
	if x < 6 then return f5; end;	f6 :=  8;
	if x < 7 then return f6; end;	f7 := 13;
	if x < 8 then return f7; end;	f8 := 21;
	if x < 9 then return f8; end;	f9 := 34;
	return f9;
end;