Var
 a,b,y:Real;
 c:boolean;

Begin
 Repeat
  c:=true;
  Write('a = ');
  Readln(a);
  Write('b = ');
  Readln(b);
  if a=b then
   begin
    c:=false;
    Writeln('Error: a can not be equal to b!');
   end
  else
  if a=-b then
   begin
    c:=false;
    Writeln('Error: a can not be equal to -b!');
   end
  else
  if a=0 then
   begin
    c:=false;
    Writeln('Error: a can not be equal to 0!');
   end
  else
  if b=0 then
   begin
    c:=false;
    Writeln('Error: b can not be equal to 0!');
   end
  else
  if a=-1 then
   begin
    c:=false;
    Writeln('Error: a can not be equal to -1!');
   end
  else
  if b=1 then
   begin
    c:=false;
    Writeln('Error: b can not be equal to 1!');
   end
  else
  if b=2 then
   begin
    c:=false;
    Writeln('Error: b can not be equal to 2!');
   end;
 Until c;

 y:=Abs(a+b)*(a+b)/((a+b)/(a-b))+(1.0+1.0/(1.0+1.0/a))/Sqr(2.0-2.0/(2.0-2.0/b));
 Writeln('y = ',y:0:5);
 Readln
End.