program palindrome;

var
    i: integer;
    count: integer;
    fwd: integer;
    back: integer;
    done: boolean;
    okay: boolean;
    tempchar: char;
    line: array[1..100] of char;

begin
  done := false;	
  while not done do
    begin
      count := 0;
      while (not eoln) do
        begin
	  read(tempchar);
	  if ((tempchar >= 'a') and (tempchar <= 'z')) then
	    begin
              count := count + 1;
              line[count] := tempchar;
            end
	  else if ((tempchar >= 'A') and (tempchar <= 'Z')) then
	    begin
              count := count + 1;
              line[count] := chr(ord(tempchar) + ord(' '));
            end;
        end;
      readln;
      if count <> 0 then
        begin  
      	  fwd := 1;
    	  back := count;
    	  okay := TRUE;

          while (fwd < back) and (okay) do
            begin
              if line[fwd] <> line[back] then
		begin
	          okay := FALSE;
                end;
              fwd := fwd + 1;  
              back := back - 1;  
            end;

          if okay then 
	    writeln('YES')
          else
            writeln('NO');
	end
      else (* blank line entered *)
	begin
	  done := TRUE;
	end;
    end;
end.