从父子结构创建完整的层次结构字符串算法，递归

class Node:
    def __init__(self, name, parent=None):
        self.name = name
        self.parent = parent
        self.children = []

    def add_child(self, child):
        self.children.append(child)
        child.parent = self

def build_hierarchy_string(node, level=0):
    hierarchy_str = "\t" * level + node.name + "\n"
    for child in node.children:
        hierarchy_str += build_hierarchy_string(child, level + 1)
    return hierarchy_str

# 示例用法
root = Node("Root")
child1 = Node("Child1")
child2 = Node("Child2")
subchild1 = Node("SubChild1")

root.add_child(child1)
root.add_child(child2)
child1.add_child(subchild1)

print(build_hierarchy_string(root))