C++ 错误LNK2005-我在这里做错了什么？
我已经得到了一些我应该修改的源代码（作为任务的一部分），但我无法编译未修改的代码版本，我正在抓狂。（需要明确的是-此代码用于学校哈希表作业，这些编译错误不是作业的一部分） 我正在使用VisualStudio2010进行编译。我整天都在做这件事，结果一事无成 我收到一系列“LNK2005”错误： 这会产生以下错误：C++ 错误LNK2005-我在这里做错了什么？,c++,linker-errors,lnk2019,lnk2005,C++,Linker Errors,Lnk2019,Lnk2005,我已经得到了一些我应该修改的源代码（作为任务的一部分），但我无法编译未修改的代码版本，我正在抓狂。（需要明确的是-此代码用于学校哈希表作业，这些编译错误不是作业的一部分） 我正在使用VisualStudio2010进行编译。我整天都在做这件事，结果一事无成 我收到一系列“LNK2005”错误： 这会产生以下错误： 1>------ Build started: Project: Assignment10, Configuration: Debug Win32 ------ 1> h
1>------ Build started: Project: Assignment10, Configuration: Debug Win32 ------
1> hashmain.cpp
1>hashtable.obj : error LNK2019: unresolved external symbol "class LinkedListSavitch::Node<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > * __cdecl LinkedListSavitch::search<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > >(class LinkedListSavitch::Node<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > *,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??$search@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@LinkedListSavitch@@YAPAV?$Node@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@0@PAV10@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z) referenced in function "public: bool __thiscall HashTableSavitch::HashTable::containsString(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)const " (?containsString@HashTable@HashTableSavitch@@QBE_NV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z)
1>hashtable.obj : error LNK2019: unresolved external symbol "void __cdecl LinkedListSavitch::headInsert<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > >(class LinkedListSavitch::Node<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > * &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??$headInsert@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@LinkedListSavitch@@YAXAAPAV?$Node@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@0@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z) referenced in function "public: void __thiscall HashTableSavitch::HashTable::put(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)" (?put@HashTable@HashTableSavitch@@QAEXV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z)
1>E:\Google Drive\CPSC 1160\Labs\Projects\Assignment10\Debug\Assignment10.exe : fatal error LNK1120: 2 unresolved externals
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
1>----构建已启动：项目：分配10，配置：调试Win32------
1> hashmain.cpp
1> hashtable.obj:错误LNK2019:未解析的外部符号“类LinkedListSavitch:：Node*u cdecl LinkedListSavitch:：search（类LinkedListSavitch:：Node*，类std:：basic_字符串常量&）”(??$search@V？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@2@@std@@@LinkedListSavitch@@YAPAV$Node@V？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@2@@std@@@0@PAV10@ABV？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@函数“public:bool\uu thiscall HashTableSavitch:：HashTable:：containssString”中引用了2@@std@@@Z）（类标准：：基本字符串）常量“（？）？containsString@HashTable@HashTableSavitch@@QBE\u NV？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@2@@@std@@@Z）
1> hashtable.obj:错误LNK2019:未解析的外部符号“void\u cdecl LinkedListSavitch:：headInsert（类LinkedListSavitch:：Node*&，类std:：basic\u string const&）”(??$headInsert@V？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@2@@std@@@LinkedListSavitch@@YAXAAPAV$Node@V？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@2@@std@@@0@ABV？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@函数“public:void\u thiscall HashTableSavitch:：HashTable:：put（类std:：basic\u字符串）中引用了2@@std@@@Z）" (?put@HashTable@HashTableSavitch@@QAEXV？$basic_string@DU？$char_traits@D@性病病毒$allocator@D@2@@@std@@@Z）
1> E:\Google Drive\CPSC 1160\Labs\Projects\Assignment10\Debug\Assignment10.exe:致命错误LNK1120:2个未解析的外部
======生成：0成功，1失败，0最新，0跳过==========
//This is the header file listtools.h. This contains type definitions and
//function declarations for manipulating a linked list to store data of any type T.
//The linked list is given as a pointer of type Node<T>* which points to the
//head (first) node of the list. The implementation of the functions are given
//in the file listtools.cpp.
#ifndef LISTTOOLS_H
#define LISTTOOLS_H
#include <cstddef>
namespace LinkedListSavitch
{
template<class T>
class Node
{
public:
Node(const T& theData, Node<T>* theLink) : data(theData), link(theLink) { }
Node<T>* getLink() const { return link; }
const T& getData() const { return data; }
void setData(const T& theData) { data = theData; }
void setLink(Node<T>* pointer) { link = pointer; }
private:
T data;
Node<T> *link;
};
template<class T>
void headInsert(Node<T>*& head, const T& theData)
{
head = new Node<T>(theData, head);
}
//Precondition: The pointer variable head points to
//the head of a linked list.
//Postcondition: A new node containing theData
//has been added at the head of the linked list.
etc etc etc...
//这是头文件listtools.h。它包含类型定义和
//用于操作链表以存储任何类型T的数据的函数声明。
//链表作为Node*类型的指针提供，指向
//列表的头（第一个）节点。给出了函数的实现
//在文件listtools.cpp中。
#ifndef列表工具
#定义列表工具
#包括
命名空间LinkedListSavitch
{
模板
类节点
{
公众：
节点（const T&theData，Node*theLink）：数据（theData），链接（theLink）{}
Node*getLink（）常量{return link；}
const T&getData（）const{return data；}
void setData（const T&theData）{data=theData；}
void setLink（节点*指针）{link=pointer；}
私人：
T数据；
节点*链接；
};
模板
无效标头插入（节点*&标头、常量和数据）
{
head=新节点（数据，head）；
}
//前提条件：指针变量head指向
//链表的头。
//后置条件：包含数据的新节点
//已添加到链接列表的开头。
等等等等等等。。。
“Unresolved External Symbol”（未解析的外部符号）基本上是说，当它转到链接时，它找不到节点的符号。问题的根源似乎是您在没有实现的情况下实例化了模板函数（您的.h试图声明，而您的.cpp试图定义它们） 您有两种解决问题的方法：
//This is the header file listtools.h. This contains type definitions and
//function declarations for manipulating a linked list to store data of any type T.
//The linked list is given as a pointer of type Node<T>* which points to the
//head (first) node of the list. The implementation of the functions are given
//in the file listtools.cpp.
#ifndef LISTTOOLS_H
#define LISTTOOLS_H
#include <cstddef>
namespace LinkedListSavitch
{
template<class T>
class Node
{
public:
Node(const T& theData, Node<T>* theLink) : data(theData), link(theLink) { }
Node<T>* getLink() const { return link; }
const T& getData() const { return data; }
void setData(const T& theData) { data = theData; }
void setLink(Node<T>* pointer) { link = pointer; }
private:
T data;
Node<T> *link;
};
template<class T>
void headInsert(Node<T>*& head, const T& theData)
{
head = new Node<T>(theData, head);
}
//Precondition: The pointer variable head points to
//the head of a linked list.
//Postcondition: A new node containing theData
//has been added at the head of the linked list.
etc etc etc...
//这是头文件listtools.h。它包含类型定义和
//用于操作链表以存储任何类型T的数据的函数声明。
//链表作为Node*类型的指针提供，指向
//列表的头（第一个）节点。给出了函数的实现
//在文件listtools.cpp中。
#ifndef列表工具
#定义列表工具
#包括
命名空间LinkedListSavitch
{
模板
类节点
{
公众：
节点（const T&theData，Node*theLink）：数据（theData），链接（theLink）{}
Node*getLink（）常量{return link；}
const T&getData（）const{return data；}
void setData（const T&theData）{data=theData；}
void setLink（节点*指针）{link=pointer；}
私人：
T数据；
节点*链接；
};
模板
无效标头插入（节点*&标头、常量和数据）
{
head=新节点（数据，head）；
}
//前提条件：指针变量head指向
//链表的头。
//后置条件：包含数据的新节点
//已在t处添加
// This is the implementation file hashtble.cpp.
// This is the implementation of the class HashTable.
#include <string>
#include "listtools.h"
#include "hashtable.h"
using LinkedListSavitch::Node;
using LinkedListSavitch::search;
using LinkedListSavitch::headInsert;
using std::string;
namespace HashTableSavitch
{
HashTable::HashTable()
{
for (int i = 0; i < SIZE; i++)
{
hashArray[i] = NULL;
}
}
HashTable::~HashTable()
{
for (int i=0; i<SIZE; i++)
{
Node<string> *next = hashArray[i];
while (next != NULL)
{
Node<string> *discard = next;
next = next->getLink( );
delete discard;
}
}
}
int HashTable::computeHash(string s)
{
int hash = 0;
for (int i = 0; i < s.length( ); i++)
{
hash += s[i];
}
return hash % SIZE;
}
bool HashTable::containsString(string target) const
{
int hash = this->computeHash(target);
Node<string>* result = search(hashArray[hash], target);
if (result == NULL)
return false;
else
return true;
}
void HashTable::put(string s)
{
int hash = computeHash(s);
if (search(hashArray[hash], s)==NULL)
{
// Only add the target if it's not in the list
headInsert(hashArray[hash], s);
}
}
} // HashTableSavitch
//This is the header file listtools.h. This contains type definitions and
//function declarations for manipulating a linked list to store data of any type T.
//The linked list is given as a pointer of type Node<T>* which points to the
//head (first) node of the list. The implementation of the functions are given
//in the file listtools.cpp.
#ifndef LISTTOOLS_H
#define LISTTOOLS_H
namespace LinkedListSavitch
{
template<class T>
class Node
{
public:
Node(const T& theData, Node<T>* theLink) : data(theData), link(theLink){}
Node<T>* getLink( ) const { return link; }
const T& getData( ) const { return data; }
void setData(const T& theData) { data = theData; }
void setLink(Node<T>* pointer) { link = pointer; }
private:
T data;
Node<T> *link;
};
template<class T>
void headInsert(Node<T>*& head, const T& theData);
//Precondition: The pointer variable head points to
//the head of a linked list.
//Postcondition: A new node containing theData
//has been added at the head of the linked list.
template<class T>
void insert(Node<T>* afterMe, const T& theData);
//Precondition: afterMe points to a node in a linked list.
//Postcondition: A new node containing theData
//has been added after the node pointed to by afterMe.
template<class T>
void deleteNode(Node<T>* before);
//Precondition: The pointers before point to nodes that has
//at least one node after it in the linked list.
//Postcondition: The node after the node pointed to by before
//has been removed from the linked list and its storage
//returned to the freestore.
template<class T>
void deleteFirstNode(Node<T>*& head);
//Precondition: The pointers head points to the first
//node in a linked list; with at least one node.
//Postcondition: The node pointed to by head has been removed
//for the linked list and its storage returned to the freestore.
template<class T>
Node<T>* search(Node<T>* head, const T& target);
//Precondition: The pointer head points to the head of a linked list.
//The pointer variable in the last node is NULL. head (first) node
//head (first) node has been defined for type T.
//(== is used as the criterion for being equal).
//If the list is empty, then head is NULL.
//Returns a pointer that points to the first node that
//is equal to the target. If no node equals the target,
//the function returns NULL.
}//LinkedListSavitch
#endif //LISTTOOLS_H
//This is the implementation file listtools.cpp. This file contains
//function definitions for the functions declared in listtools.h.
#include <cstddef>
#include "listtools.h"
namespace LinkedListSavitch
{
template<class T>
void headInsert(Node<T>*& head, const T& theData)
{
head = new Node<T>(theData, head);
}
template<class T>
void insert(Node<T>* afterMe, const T& theData)
{
afterMe->setLink(new Node<T>(theData, afterMe->getLink( )));
}
template<class T>
void deleteNode(Node<T>* before)
{
Node<T> *discard;
discard = before->getLink( );
before->setLink(discard->getLink( ));
delete discard;
}
template<class T>
void deleteFirstNode(Node<T>*& head)
{
Node<T> *discard;
discard = head;
head = head->getLink( );
delete discard;
}
//Uses cstddef:
template<class T>
Node<T>* search(Node<T>* head, const T& target)
{
Node<T>* here = head;
if (here == NULL) //if empty list
{
return NULL;
}
else
{
while (here->getData( ) != target && here->getLink( ) != NULL)
here = here->getLink( );
if (here->getData( ) == target)
return here;
else
return NULL;
}
}
}//LinkedListSavitch
#include <string>
#include <iostream>
#include "listtools.cpp" // Your compiler may compile separately
#include "hashtable.h"
//#include "hashtable.cpp" // Your compiler may compile separately
using std::string;
using std::cout;
using std::endl;
using HashTableSavitch::HashTable;
1>------ Build started: Project: Assignment10, Configuration: Debug Win32 ------
1> hashmain.cpp
1>hashtable.obj : error LNK2019: unresolved external symbol "class LinkedListSavitch::Node<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > * __cdecl LinkedListSavitch::search<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > >(class LinkedListSavitch::Node<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > *,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??$search@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@LinkedListSavitch@@YAPAV?$Node@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@0@PAV10@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z) referenced in function "public: bool __thiscall HashTableSavitch::HashTable::containsString(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)const " (?containsString@HashTable@HashTableSavitch@@QBE_NV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z)
1>hashtable.obj : error LNK2019: unresolved external symbol "void __cdecl LinkedListSavitch::headInsert<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > >(class LinkedListSavitch::Node<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > * &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??$headInsert@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@LinkedListSavitch@@YAXAAPAV?$Node@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@0@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z) referenced in function "public: void __thiscall HashTableSavitch::HashTable::put(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)" (?put@HashTable@HashTableSavitch@@QAEXV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z)
1>E:\Google Drive\CPSC 1160\Labs\Projects\Assignment10\Debug\Assignment10.exe : fatal error LNK1120: 2 unresolved externals
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
//This is the header file listtools.h. This contains type definitions and
//function declarations for manipulating a linked list to store data of any type T.
//The linked list is given as a pointer of type Node<T>* which points to the
//head (first) node of the list. The implementation of the functions are given
//in the file listtools.cpp.
#ifndef LISTTOOLS_H
#define LISTTOOLS_H
#include <cstddef>
namespace LinkedListSavitch
{
template<class T>
class Node
{
public:
Node(const T& theData, Node<T>* theLink) : data(theData), link(theLink) { }
Node<T>* getLink() const { return link; }
const T& getData() const { return data; }
void setData(const T& theData) { data = theData; }
void setLink(Node<T>* pointer) { link = pointer; }
private:
T data;
Node<T> *link;
};
template<class T>
void headInsert(Node<T>*& head, const T& theData)
{
head = new Node<T>(theData, head);
}
//Precondition: The pointer variable head points to
//the head of a linked list.
//Postcondition: A new node containing theData
//has been added at the head of the linked list.
etc etc etc...
// Program to demonstrate use of the HashTable class
#include <string>
#include <iostream>
//#include "listtools.cpp" // Your compiler may compile separately
#include "hashtable.h"
//#include "hashtable.cpp" // Your compiler may compile separately
using std::string;
using std::cout;
using std::endl;
using HashTableSavitch::HashTable;