实现一个简单的计算器,包含了 一定的逻辑判断,界面新颖.操作简单.适合刚学vc的孩子-implement a simple calculator, contains a certain logic judgment, new interface. simple operation. just learning for the children to see vc

树的递归与非递归三序遍历，计算树的繁茂度和交换树的左右孩子并输出。-Tree recursive and non recursive traversal of the three order, the calculation of the tree s lush and exchange trees around the child and output