def dump_permutation_of_source_array(tree):
    if (tree.root != None):
        _dump_permutation_of_source_array([tree.root], [])
    else:
        print('tree is empty')
def dump_permutation_of_source_array(tree):
    if (tree.root != None):
        _dump_permutation_of_source_array([tree.root], [])
    else:
        print('tree is empty')