> // 1028 Web Navigation.cpp : 定义控制台应用程序的入口点。
> //
> 
> #include "stdafx.h"
> #include <iostream>
> #include <string>
> 
> using namespace std;
> 
> struct Node
> {
> 	string site;
> 	Node* pre;
> 	Node* next;
> };
> 
> void Insert( Node* &cur, Node* &b, Node* &f, const string site )
> {
> 	// 新建节点
> 
> 	Node* s = new Node();
> 	s->site = site;
> 	s->pre = cur;
> 	s->next = NULL;
> 
> 	// 连
> 
> 	cur->next = s;
> 	b = cur;
> 	cur = s;
> 
> 	// 删除f之后所有节点
> 
> 	while( f )
> 	{
> 		Node* p = f->next;
> 		delete f;
> 		f = p;
> 	}
> }
> 
> bool Back( Node* &cur, Node* &b, Node* &f )
> {
> 	if( b )
> 	{
> 		f = cur;
> 		cur = b;
> 		b = b->pre;
> 		return true;
> 	}
> 	else
> 		return false;
> }
> 
> bool Forward( Node* &cur, Node* &b, Node* &f )
> {
> 	if( f )
> 	{
> 		b = cur;
> 		cur = f;
> 		f = f->next;
> 		return true;
> 	}
> 	else
> 		return false;
> }
> 
> void ShowCur( const Node* cur, const bool flag )
> {
> 	if( flag ) 
> 		cout << cur->site << endl;
> 	else
> 		cout << "Ignored\n";
> }
> 
> void Dispose( Node* &cur, Node* &b, Node* &f )
> {
> 	while( b )
> 	{
> 		Node* p = b->pre;
> 		delete b;
> 		b = p;
> 	}
> 
> 	delete cur;
> 	cur = NULL;
> 
> 	while( f )
> 	{
> 		Node* p = f->next;
> 		delete f;
> 		f = p;
> 	}
> }
> 
> int main()
> {
> 	Node* cur = new Node();
> 	cur->site = "http://www.acm.org/";
> 	cur->pre = NULL;
> 	cur->next = NULL;
> 	Node* b = cur->pre;
> 	Node* f = cur->next;
> 
> 	string cam, buff;
> 	cin >> cam;
> 	while( cam != "QUIT" )
> 	{
> 		char ch = getchar();
> 		if( ch == ' ' )
> 		{
> 			cin >> buff;
> 		}
> 		bool flag = true;
> 		if( cam == "VISIT" )
> 			 Insert( cur, b, f, buff );
> 		else if( cam == "BACK" )
> 			flag = Back( cur, b, f );
> 		else if( cam == "FORWARD" )
> 			flag = Forward( cur, b, f );
> 		ShowCur( cur, flag );
> 		cin >> cam;
> 	}
> 	// 释放链表
> 	Dispose( cur, b, f );
> 
> 
> 	system("pause");
> 	return 0;
> }
> 

• Re:可以用二维数组做，代码少点！ (656) huangchang9001 2011-03-25 21:30:41