program zadacha1;

{$APPTYPE CONSOLE}

uses
  SysUtils;

var r,s :real;
begin
writeln('vvedit r ');
readln(r);
s:=2*pi*sqr(r);
r:=1;
while r<=18 do
begin
r:=r+1;
writeln('s= ',s:1:3);
end;
readln;
end.