var
  a : string;
  i, j, size : longint;
  f : boolean;
function p(fpos, size : longint; a: string) : boolean;
var
  b : string;
  n : longint;
begin
  b := '';
  p := False;
  for n := length(a) downto 1 do
    b := b + a[n];
  if a = b then
    p := True;
end;
begin
  f := False;
  readln(a);
  for i := 1 to length(a) - 1 do
    for j := 2 to length(a) - i + 1 do
      if p(i, j, a) = True then
        f := True;
  if f then
    writeln('YES')
  else
    writeln('NO');
end.