用非递归法实现二叉树的遍历 非递归算法中,必须设置堆栈,可以直接用一维数组来代替栈,但必须另外设置栈顶指针。 -Non-recursive method of binary tree traversal non-recursive algorithm, you must set the stack, which enables the direct use of one-dimensional array instead of the stack, but must also set t