load_doc D1 list.lht
load_doc D2 list.lht
root N1 D1
root N2 D2

echo Original 1:
print_tree N1
echo Original 2:
print_tree N2

list_child N1
list_next N1
list_child N2
list_next N2


tree_merge N1 N2
echo After merging the two non-empty lists:


root N1 D1
root N2 D2

echo Original 1:
print_tree N1
echo Original 2:
print_tree N2

free_doc D1
free_doc D2
