uses crt;
type matr=array[1..6,1..6] of integer;
     vek=array[1..6] of integer;
var x:matr;
    v1,v2,v:vek;
    a,u,h,k,d,b,c,i,n,m,j:integer;
    f,g:text;
function max(i,j:integer):integer;
var a:integer;
begin
a:=0;
for h:= 1 to i do
 for k:= 1 to j do
  if x[h,k]>a then a:=x[h,k];
max:=a;
end;
begin
clrscr;
assign(f,'cmlsc.in');
reset(f);
read(f,n,m);
for i:= 1 to n do
 read(f,v1[i]);
for j:= 1 to m do
 read(f,v2[j]);
for i:=1 to n do
 for j:= 1 to m do
  if v1[i]=v2[j] then x[i,j]:=max(i-1,j-1)+1;
c:=max(n,m);
h:=n;
u:=m;
k:=0;
assign(g,'cmlsc.out');
rewrite(g);
writeln(g,c);
while k<c do
begin
inc(k);
d:=0;
for i:= 1 to h do
for j:= 1 to u do
 begin
  if x[i,j]>d then begin
                        a:=i;
                        b:=j;
                        d:=x[i,j];
                    end;
                    end;
v[k]:=v1[a];
h:=a-1;
u:=j-1;
end;
for i:= k downto 1 do
write(g,v[i],' ');
close(g);
close(f);
end.