基于多叉树后序遍历的VB实现方法。本方法有效解决复杂拓扑关系的分析，可广泛用于流域洪水演算和水资源配置中-VB method based on multi-tree postorder traversal. This method is effective to solve complex topological analysis of the relationship can be widely used in the river basin flood routing and allocat