Program Subsir;  
type Matrix= array[1..1024,1..1024] of integer; 
Vector= array[1..1024] of integer; 
var D,B:Matrix; 
T,S,C:Vector; 
k,n,m,i,j,x,y,z:integer; 
f1,f2:text; 
 
Procedure Afisare(k,h:integer ) ; 
begin
if B[k,h]=1 then begin Afisare(k-1,h-1); write(f2,T[k],' '); end
else
if B[k,h]=2 then Afisare(k-1,h) 
else
if B[k,h]=3 then Afisare(k,h-1); 
end; 
 
begin 
assign(f1,'cmlsc.in'); reset(f1); 
assign(f2,'cmlsc.out'); rewrite(f2); 
readln(f1,n,m); 
for i:=0 to n+1 do
for j:=0 to m+1 do
D[i,j]:=0; 
 
for i:=1 to n do
read(f1,T[i]); 
for i:=1 to m do
read(f1,S[i]); 
 
for i:=1 to n do
for j:=1 to m do
if T[i]=S[j] then begin D[i,j]:=D[i-1,j-1]+1; B[i,j]:=1; end
else
if D[i-1,j]>D[i,j-1] then
begin
D[i,j]:=D[i-1,j]; 
B[i,j]:=2; 
end
else
begin
D[i,j]:=D[i,j-1]; 
B[i,j]:=3; 
end; 
z:=D[1,1]; 
for i:=1 to n do
for j:=1 to m do
if D[i,j]>=z then begin z:=D[i,j]; x:=i; y:=j; end; 
 
writeln(f2,z); 
 
Afisare(n,m); 
 
close(f1); close(f2); 
end.