var
s:string;
i,m,n:integer;
yesorno:boolean;
begin
readln(s);
{s:='hggsdjs';}
m:=length(s);
n:=m div 2;
yesorno:=true;
for i:=1 to n do
if s[i]<>s[m+1-i] then begin yesorno:=false; break; end;
if yesorno then writeln('yes') else writeln('no');
end.
program huiwen(input,output);
var a:string;i,b,n:integer;
begin
read(a);
b:=length(a);
n:=0;
for i:=1 to b do
begin
if a[i]=a[b+1-i] then n:=n+1
end;
if n=b then write('Yes') else write('No');
readln;
end.