递归函数编程的优点时简单 但耗用空间很大 由于频繁的调用函数 时间耗用也很可观 这个算法可以在空间和时间上解决递归函数的缺点 -The advantages of recursive functions when programming simple but frequent consumption is much room for the call function as a result of time spent in this algorithm is also very good in