fun fives len =
    if len = 0 then
       []
    else
       5 :: fives (len-1);

fun makeList elt len =
    if len = 0 then
       []
    else
       elt :: makeList elt (len-1);

fun makeList2 (elt, len) =
    if len = 0 then
       []
    else
       elt :: makeList2 (elt, (len-1));

fun sum integers =
    if null integers then
       0
    else
       (hd integers)+(sum (tl integers));

fun sumReals reals =
    if null reals then
       0.0
    else
       (hd reals)+(sumReals (tl reals));