Because in process of mining only generate constrained sub-trees consisting of three small arrays,which is pseudo tree structure based on the originally unidirectional FP-tree,the flaw is avoided in former algorithms which need to generate lots of condi.
该算法在挖掘过程中只生成被约束子树,而它是一种虚拟的树结构,在原有的单向FP-tree基础上用三个很小的数组来表示,因而避免了以往算法需递归构造条件FP-tree来计算频繁闭项集的弊端,极大地降低了内存空间和时间开销,提高了挖掘效率。