var
n, i : integer; str : string; isPlalindrome : boolean;
begin readln(str);
n := Length(str);
isPlalindrome := true;
for i := 1 to (n div 2) do begin
if (str[i] <> str[n-i+1]) then
isPlalindrome := false;
end;
if (isPlalindrome) then writeln('Yes')
else
writeln('No');
end.
输入：abceecba
输出：YES