C++primer一书的问题

[coolcoffee4051982]

编译环境，VS2008，就是书中的例子，/*
* This file contains code from "C++ Primer, Fourth Edition", by Stanley B.
* Lippman, Jose Lajoie, and Barbara E. Moo, and is covered under the
* copyright and warranty notices given in that book:
*
* "Copyright (c) 2005 by Objectwrite, Inc., Jose Lajoie, and Barbara E. Moo."
*
*
* "The authors and publisher have taken care in the preparation of this book,
* but make no expressed or implied warranty of any kind and assume no
* responsibility for errors or omissions. No liability is assumed for
* incidental or consequential damages in connection with or arising out of the
* use of the information or programs contained herein."
*
* Permission is granted for this code to be used for educational purposes in
* association with the book, given proper citation if and when posted or
* reproduced.Any commercial use of this code requires the explicit written
* permission of the publisher, Addison-Wesley Professional, a division of
* Pearson Education, Inc. Send your request for permission, stating clearly
* what code you would like to use, and in what specific way, to the following
* address:
*
* Pearson Education, Inc.
* Rights and Contracts Department
* 75 Arlington Street, Suite 300
* Boston, MA 02216
* Fax: [phone]
*/

#include "algs_preamble.h"
#include <fstream>
using std::ifstream;
#include <cstddef>
using std::size_t;

// comparison function to be used to sort by word length
bool isShorter(const string &s1, const string &s2)
{
return s1.size() < s2.size();
}

// determine whether a given word is greater than length 6
// will reimplement later as a more general version using function objects
bool GT6(const string &s)
{
return s.size() >= 6;
}

inline double
percent(double numerator, double denominator)
{
return 100 * numerator/denominator;
}

// report number of words greater than 6
// later chapter will reimplement to be more general
void report_complexity(vector<string>::iterator beg,
vector<string>::iterator end,
ostream &output = cout)
{

vector<string>::difference_type cnt =
count_if(beg, end, GT6);

output << "Number of unique words in the input "
<< end - beg << endl;
output << cnt << " "
<< make_plural(cnt, "word", "s")
<< " 6 characters or longer" << endl;
output << "Percentage of words 6 characters or more "
<< percent(cnt, end - beg) << endl;
}

ifstream &open_file(ifstream&, const string&);

ifstream &prompt_user(ifstream &stream)
{
// loops until we get a valid stream or the user asks to quit
while (true) {
// ask for name of the file to open
string filename;
cout << "Please enter file name."
<< "Hit Enter to quit: \n";
getline(cin, filename); // read the filename
// terminate the loop on either empty line or eof
if (!cin || filename == "") {
// set condition state to indicate failure & eof
stream.setstate(
ifstream::eofbit | ifstream::failbit);
return stream;
}

// use getline in case user enters a filename with spaces
if (open_file(stream, filename)) return stream;

// otherwise, stream wasn't valid, prompt user to try again
cerr << "oops! unable to open file"
<< filename
<< " please try again!" << endl;
}
}

// calls open_file to ask the user for the next book to process
// builds a vector<book> that contains the contents of each book
vector<string> get_books()
{
ifstream infile; // stream bound to the next book file
vector<string> ret; // data structure we'll return to our caller

// prompt_user asks user for next book and binds infile to it
while (prompt_user(infile)) {

// iterator to read the text of the book
istream_iterator<string> in_iter(infile), eos;

// read contents of the book into this book's vector
ret.insert(ret.end(), in_iter, eos);

infile.close(); // close the file when we're done with it
}
return ret;
}


int main()
{
// read the contents of the books to analyze
vector<string> words = get_books();

// sort the input so that we can eliminate duplicates
sort(words.begin(), words.end());

// unique reorders elements and returns iterator to end of unique range
// erase uses that iterator to erase non-unique elements
words.erase(unique(words.begin(), words.end()),
words.end());

// sort the words by size, but maintain alphabetic order for words of the same size
stable_sort(words.begin(), words.end(), isShorter);

// analyze complexity: report frequency of words of each size
// and total number/% of words greaten than length 6
report_complexity(words.begin(), words.end());

return 0;
}

[coolcoffee4051982]

提示的错误如下：
1>------ 已启动生成: 项目: test, 配置: Debug Win32 ------
1>正在编译...
1>test.cpp
1>正在链接...
1> 正在创建库 D:\Backup\Visual Studio 2008\Projects\test\Debug\test.lib 和对象 D:\Backup\Visual Studio 2008\Projects\test\Debug\test.exp
1>test.obj : error LNK2019: 无法解析的外部符号 "class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __cdecl make_plural(unsigned int,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (?make_plural@@YA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@IABV12@0@Z)，该符号在函数 "void __cdecl report_complexity(class std::_Vector_iterator<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::allocator<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > >,class std::_Vector_iterator<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::allocator<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > > >,class std::basic_ostream<char,struct std::char_traits<char> > &)" (?report_complexity@@YAXV?$_Vector_iterator@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@V?$allocator@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@2@@std@@0AAV?$basic_ostream@DU?$char_traits@D@std@@@2@@Z) 中被引用
1>test.obj : error LNK2019: 无法解析的外部符号 "class std::basic_ifstream<char,struct std::char_traits<char> > & __cdecl open_file(class std::basic_ifstream<char,struct std::char_traits<char> > &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (?open_file@@YAAAV?$basic_ifstream@DU?$char_traits@D@std@@@std@@AAV12@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@2@@Z)，该符号在函数 "class std::basic_ifstream<char,struct std::char_traits<char> > & __cdecl prompt_user(class std::basic_ifstream<char,struct std::char_traits<char> > &)" (?prompt_user@@YAAAV?$basic_ifstream@DU?$char_traits@D@std@@@std@@AAV12@@Z) 中被引用
1>D:\Backup\Visual Studio 2008\Projects\test\Debug\test.exe : fatal error LNK1120: 2 个无法解析的外部命令
1>生成日志保存在“file://d:\Backup\Visual Studio 2008\Projects\test\test\Debug\BuildLog.htm”
1>test - 3 个错误，0 个警告
========== 生成: 成功 0 个，失败 1 个，最新 0 个，跳过 0 个 ==========