program Project2;
 
{$APPTYPE CONSOLE}
 
uses
  SysUtils,
  Math;
 
var n,r:integer;
    y:real;
begin
write ('Vvedite` n=');
readln (n);
r:=0;y:=1;
while y<=n do
   begin
     y:=power(2,r);
     r:=r+1;
   end;
write ('y=', y:0:0);
readln
end.