(* Given a positive (even) integer,this program calculates
   all the integer side lengths of right rectangular prisms that have the same
   surface area.  For example a surface area of 54 square units is enjoyed
   by rectangular prisms of dimensions 1x1x13, 1x3x6, and 3x3x3.
   This program is more enjoyable if one first tries to figure out, on
   a chalkboard for instance, the triples that give the same surface areas as cubes,
   like the 3x3x3 cube, as a challenge.

   Programmer: Robert Simms of Salisbury, MD
   Date:       about 1993
   Language:   (VAX)Pascal
*)

program sfc(input, output);
var
   s, s2: integer;
   x, y: integer;
   z: integer;

begin
write('Enter a surface area: ');
while not (eoln or eof) do
   begin
   readln(s);
   s2 := s div 2;
   if (s mod 2) = 1 then
      writeln('Surface area must be even --> ',(s2*2):0);

   for x := 2-(s2 mod 2) to trunc(sqrt(s2/3)) do
      for y := x to trunc(-x+sqrt(x**2+s2)) do
         if ((s2 -x*y) mod (x+y)) = 0 then
            writeln(x, y, (s2-x*y) div (x+y));
   write('Enter a surface area: ')
  end
end.