program uniokepzes;
uses tomb_io;
var  a,b,c:tomb;
     n,m,i,j,k:byte;
begin
  beolvas(a,n,'a');
  beolvas(b,m,'b');
  kiir(a,n,'a');
  kiir(b,m,'b');
  for i:=1 to n do
    c[i]:=a[i];
  k:=n;
  for j:=1 to m do
  begin
    if not talal(a,n,b[j])and not talal(c,k,b[j]) then
    begin
      k:=k+1;
      c[k]:=b[j];
    end;
  end;
  kiir(c,k,'c');
  readln;
end.