var
node: tyunode;
begin
if brother = nil then
if ffirstnode = nil then
begin
result := tyunode.create(self);
ffirstnode := result;
exit;
end
else
brother := ffirstnode;
node := brother.getlastbrother;
result := tyunode.create(self);
node.fdownright := result;
result.fupright := node;
end;
function tyutree.addchild(parent: tyunode): tyunode;
var
node: tyunode;
begin
if parent = nil then
begin
result := add(nil);
exit;
