Program Palindrom;
   Var a,y            : array[0..101] of longint;
       p,m,d,b,h,o,w  : longint;
       fi,fo          : text;

Procedure Inp;
  Var i,x : longint;
Begin
  Assign(fi,'palindro.dat');
  Reset(fi);
  Readln(fi,p);
  i:=1;
  x:=p+1;
  While i<x do begin
     Read(fi,a[i]);
     i:=i+1;
  end;
  Close(fi);
End;{INP}

Procedure Out;
Begin
   Assign(fo,'palindro.sol');
   Rewrite(fo);
   Writeln(fo,p);
   While p>0 do begin
      Write(fo,y[p]);
      p:=p-1;
      Write(fo,' ');
   end;
   Close(fo);
End;{INP}

Function Sim (Var t : array of longint; f : longint) : longint;
   Var s,j : longint;
       u   : real;
Begin
   s:=3;
   j:=1;
   u:=f/2;
 While (s>1) and (f>u) do begin
   if a[j] <> a[f] then begin
      s:=1;
   end;
   f:=f-1;
   j:=j+1;
 end;
Sim:=s;
End;{SIM}

Begin
Inp;
m:=Sim(a,p);
b:=1;
d:=p;
h:=p;
o:=1;
w:=1;
   While m<>3 do begin
    While o<>0 do begin
        a[d+w]:=a[o];
        w:=w+1;
        o:=o-1;
    end;
      y[b]:=a[b];
      b:=b+1;
      h:=h+1;
      m:=Sim(a,h);
      o:=b;
      w:=1;
   end;
p:=b-1;
Out;
End.