C++ 将未排序的链接列表转换为已排序的链接列表?(C+;+;)
我在尝试将INSERT函数转换为按字母顺序对节点排序的函数时遇到问题。我已经写下了我到目前为止所做的尝试……但它只检查第一个节点的名称,看它是否大于函数参数中新节点的给定名称。有人能告诉我,我将如何通过每个节点移动,并能够比较它们的键(名称),并相应地将它们放置在左右?下面是我的代码和我的INSERT函数中的内容C++ 将未排序的链接列表转换为已排序的链接列表?(C+;+;),c++,list,C++,List,我在尝试将INSERT函数转换为按字母顺序对节点排序的函数时遇到问题。我已经写下了我到目前为止所做的尝试……但它只检查第一个节点的名称,看它是否大于函数参数中新节点的给定名称。有人能告诉我,我将如何通过每个节点移动,并能够比较它们的键(名称),并相应地将它们放置在左右?下面是我的代码和我的INSERT函数中的内容 // UnSortedLnkList.h //---------------------------- #include <iostream>
// UnSortedLnkList.h
//----------------------------
#include <iostream>
#include <afxwin.h>
using namespace std;
#define new DEBUG_NEW
struct Node {
string m_name; // key
int m_age;
Node* m_next;
Node(const string& name, int age, Node* next = NULL);
};
ostream& operator<< (ostream&, const Node&);
class ULnkList {
friend ostream& operator<< (ostream&, const ULnkList&); // 1.5
public:
ULnkList();
// copy ctor
ULnkList(const ULnkList& existingList ); // 5
~ULnkList(); // 4
bool IsEmpty() const;
int Size() const;
bool Insert(const string& name, int age); // 1
bool Delete(const string& name); // 3
bool Lookup(const string& name, int& age) const; // 2
ULnkList& operator =(const ULnkList& list2); // 6
bool Delete2(const string& name);
private:
Node* m_head; // points to head of the list
int m_num; // the number of entries in the list
// helper functions:
void Clear(); // 7
void Copy(const ULnkList& list2); // 8
};
// UnSortedLnkList.cpp
//----------------------------
#include "UnSortedLnkList.h"
#include <iostream>
#include <string>
using namespace std;
Node::Node(const string& name, int age, Node* next)
: m_name(name), m_age(age), m_next(next)
{}
ostream& operator<< (ostream& os, const Node& n) // cout << n;
{
os << "Name: " << n.m_name << "\tAge: " << n.m_age;
return os;
}
ULnkList::ULnkList()
: m_head(new Node("",-99,NULL)), m_num(0)
{
//m_head = new Node("",-99,NULL);
}
//
ULnkList::ULnkList(const ULnkList& existingList )
{
Copy(existingList);
}
void ULnkList::Copy(const ULnkList& existingList)
{
m_num = existingList.m_num;
// create dummy node
m_head = new Node("",-99,NULL);
// traverse existing list
Node *pe = existingList.m_head->m_next;
Node *pThis = m_head;
while( pe != 0)
{
// create a copy of the Node in OUR list
pThis->m_next = new Node(pe->m_name,pe->m_age,0);
// update pointers
pe = pe->m_next;
pThis = pThis->m_next;
}
}
void ULnkList::Clear()
{
Node *p = m_head->m_next;
Node *tp = m_head; // trail pointer
while( p != 0)
{
delete tp;
// update pointers
tp = p; //
p = p->m_next;
}
delete tp;
}
ULnkList& ULnkList::operator =(const ULnkList& list2) // list1 = list2;
{
// list1 = list1; // check for self-assignment
if( this != &list2 )
{
this->Clear(); // normally Clear();
this->Copy(list2);
}
// l1 = l2 = l3;
return *this;
}
bool ULnkList::IsEmpty() const
{
return m_num == 0;
// return m_head->m_next == NULL;
}
int ULnkList::Size() const
{
return m_num;
}
//
ULnkList::Insert(const string& name, int age)
{
Node *current = m_head->m_next;
Node *previous = m_head;
if (m_head->m_next == NULL)
{
m_head->m_next = new Node(name,age,m_head->m_next);
m_num++;
return true;
}
if (name < m_head->m_next->m_name)
{
m_head->m_next = new Node(name,age,m_head->m_next);
m_num++;
return true;
}
return true;
}
//
ostream& operator<< (ostream& os, const ULnkList& list) // cout << list;
{
Node *p = list.m_head->m_next; // first node with data
while( p != 0 )
{
cout << *p << endl; // ????
// update p
p = p->m_next;
}
cout << "--------------------------------------" << endl;
return os;
}
// input: name
//// output: age if found
bool ULnkList::Lookup(const string& name, int& age) const
{
// linear search
Node *p = m_head->m_next;
while( p != 0)
{
if( name == p->m_name )
{
// found it
age = p->m_age;
return true;
}
// update p
p = p->m_next;
}
return false;
}
//
bool ULnkList::Delete(const string& name)
{
Node *p = m_head->m_next;
Node *tp = m_head; // trail pointer
while( p != 0)
{
if( name == p->m_name )
{
// found it, so now remove it
// fix links
tp->m_next = p->m_next;
// delete the node
delete p;
return true;
}
// update pointers
tp = p; // tp = tp->m_next;
p = p->m_next;
}
return false;
}
bool ULnkList::Delete2(const string& name)
{
Node *p = m_head;
while( p->m_next != 0 ) // ?????
{
if( p->m_next->m_name == name )
{
Node *save = p->m_next;
// remove the node
// fix links
p->m_next = p->m_next->m_next;
// delete memory
delete save;
return true;
}
// update pointers
p = p->m_next;
}
return false;
}
//
ULnkList::~ULnkList()
{
Clear();
}
//
//UnSortedLnkList.h
//----------------------------
#包括
#包括
使用名称空间std;
#定义新调试\u新
结构节点{
字符串m_name;//键
int m_年龄;
Node*m_next;
节点(常量字符串和名称,整数年龄,节点*下一个=NULL);
};
ostream&Operator_next;
}
删除tp;
}
ULnkList&ULnkList::operator=(const-ULnkList&list2)//list1=list2;
{
//list1=list1;//检查自分配
如果(此!=&list2)
{
此->清除();//正常清除();
此->复制(列表2);
}
//l1=l2=l3;
归还*这个;
}
bool ULnkList::IsEmpty()常量
{
返回m_num==0;
//返回m_head->m_next==NULL;
}
int ULnkList::Size()常量
{
返回m_num;
}
//
ULnkList::Insert(常量字符串和名称,整数)
{
节点*current=m_head->m_next;
节点*previous=m_头;
如果(m_head->m_next==NULL)
{
m_head->m_next=新节点(名称、年龄、m_head->m_next);
m_num++;
返回true;
}
如果(名称m_下一步->m_名称)
{
m_head->m_next=新节点(名称、年龄、m_head->m_next);
m_num++;
返回true;
}
返回true;
}
//
ostream&Operator_next;
}
返回false;
}
//
bool ULnkList::Delete(常量字符串和名称)
{
节点*p=m_头->m_下一步;
Node*tp=m_head;//跟踪指针
while(p!=0)
{
如果(名称==p->m_名称)
{
//找到了,现在把它移除
//固定链接
tp->m_next=p->m_next;
//删除节点
删除p;
返回true;
}
//更新指针
tp=p;//tp=tp->m_next;
p=p->m_下一步;
}
返回false;
}
布尔ULnkList::Delete2(常量字符串和名称)
{
节点*p=m_头;
而(p->m_next!=0)/?????
{
如果(p->m_next->m_name==name)
{
节点*save=p->m_next;
//删除节点
//固定链接
p->m_next=p->m_next->m_next;
//删除内存
删除保存;
返回true;
}
//更新指针
p=p->m_下一步;
}
返回false;
}
//
ULnkList::~ULnkList()
{
清除();
}
//
我猜这是家庭作业,所以我不打算写代码。我建议您的Insert()函数可以通过比较输入字符串,然后执行Insert逻辑,从头到尾遍历列表,直到找到“正确”的位置。这是假设您必须使用文本列表作为数据结构。如果希望平均插入性能更好,可以使用二叉树作为底层结构,但这会使列表遍历更复杂。您的问题在于以下代码:
if (name < m_head->m_next->m_name)
{
m_head->m_next = new Node(name,age,m_head->m_next);
m_num++;
return true;
}
这将以升序排序的方式插入。
我还没有测试过,但请告诉我它是否有效!希望这有帮助 对于这段代码,我有一句忠告
if(name > m_head->m_name ){
while(name > current->m_next->m_name){
current = current->m_next;
}
// add temp = current->next
current->m_next = new Node(name,age)
// current->next->next = temp
您不希望在插入位置后丢失列表。如果这是家庭作业,请将其标记为家庭作业。否则,不要使用链表生成一个蹩脚的模仿
std::set
(好吧,我没有仔细看——可能它是一个蹩脚的模仿std::multiset
)。哦,既然您没有编写模板,那么也要从代码中删除this->
。
if(name > m_head->m_name ){
while(name > current->m_next->m_name){
current = current->m_next;
}
// add temp = current->next
current->m_next = new Node(name,age)
// current->next->next = temp