// палиндром
var s, substr, maxsubstr:string;
	maxcount, count, i, flag:integer;
begin
	readln(s);
	flag := 0;

	for i:=1 to length(s) do
		begin
		// 1 & length(s)
		// 2 & length(s) - 1
		if s[i] <> s[length(s) - i + 1] then
			begin
			writeln("NO");
			flag := 1;
			break;
			end;
		end;

	if(flag = 0) then
		writeln("YES");

end.