wex13_20.cpp

数据结构C++代码,经典代码,受益多多,希望大家多多支持

#include <iostream.h>
#pragma hdrstop

#include "treenode.h"
#include "treelib.h"
#include "treeprnt.h"
#include "stack.h"

void printchar(char& item)
{
	cout << item << "  ";
}

template <class T>
void Postorder_I(TreeNode<T> *t, void visit(T& item))
{
	Stack<TreeNode<T> *> S;
	TreeNode<T> *child;
	int state = 0;
	
	for(;;)
	{
		if (state == 0)
		{
			if (t != NULL)
			{
				S.Push(t);
				t = t->Left();
			}
			else
				state = 1;
		}
		else
		{
			if (S.StackEmpty())
				break;
			child = t;
			t = S.Peek();
			if (child == t->Left() && t->Right() != NULL)
			{
				t = t->Right();
				state = 0;
			}
			else
			{
				visit(t->data);
				S.Pop();
			}
		}
	}
}

void main(void)
{
	TreeNode<char> *root;
	
	MakeCharTree(root, 0);
	PrintTree(root,0);
	cout << endl;
	Postorder_I(root,printchar);
	cout << endl;
}

/*
<Run>

      C
            E
A
            D
      B

D  B  E  C  A
*/