program Ploschadj;
{$APPTYPE CONSOLE}
uses SysUtils, Math, System;
var i:integer; a:real;
begin
write('Naberi dlinu okruzhnosti : ');
readln(i);
a:=(i/2*pi);
writeln('Radius:', a);
a:=pi*a*a;
writeln('Ploschadj:', a);
writeln('Dla zaversinia nazhmi Enter!');
readln;
end.