const p=3.1415926535897932384626433832795;
var arccos,x,as,at,ah,a,b,l,r:real;

begin
read(l,r);
if r>=l*sqrt(2) then
  writeln(l*l:0:3)
else
  if r<=l / 2 then
    writeln(p*r*r:0:3)
  else
    begin

      x:=l/(2*r);
      b:=l/2;
      ArcCos := ArcTan (sqrt (1-sqr (x)) /x);
      as:=arccos*r*r;
      at:=b*sqrt(r*r-b*b);
      ah:=as-at;
      a:=p*r*r;
      a:=a-4*ah;
      writeln(a:0:3);
    end;
end.


i tested it with BP 7.0 and FP 1.0.10 both on windows... what's wrong?

754129 18:57:25
7 фев 2005 TECTOBOP 1084 Pascal Wrong Answer 6 0.015 143 КБ

1.'as' is keyword like 'while' or 'if'
2.to have AC 'if r>=l*sqrt(2) then' ---> 'if r>=l*sqrt(2)/2 then'