《C++大学教程》中关于运算符重载的一个例程

《C++大学教程（第二版）》第八章关于"<<"和">>"的重载的实例如下：

#include <iostream>

#include <iomanip>



class PhoneNumber{

	friend ostream &operator<<(ostream&, const PhoneNumber&);

	friend istream &operator>>(istream &, PhoneNumber &);

private:

	char areaCode[4];

	char exchange[4];

	char line[5];

};

ostream &operator<<(ostream &output,const PhoneNumber & num)

{

	output << "(" << num.areaCode <<") "

		<< num.exchange << "-" << num.line;

	return output;

}

istream &operator>>(istream &input, PhoneNumber & num)

{

	input.ignore();

	input >> setw(4) >>num.areaCode;

	input.ignore(2);

	input >> setw(4) >> num.exchange;

	input.ignore();

	input >> setw(5) >> num.line;

	return input;

}



int main()

{

	PhoneNumber phone;

	cout << "Enter a phone number in the form of (123) 456-789:\n";

	cin >> phone;

	cout << "The phone number entered was: " << phone <<endl;

	return 0;

}

上述代码中，除了注释没有copy过来，以及#include <iostream>和#include <iomanip>中没有加“.h”标示，其余都一样。
如果加了.h标示，则会报错说找不到文件。
然而把.h标示去掉后，报了27个错误：

1>fig08_03.cpp

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(5) : error C2143: syntax error : missing ';' before '&'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(5) : error C2433: 'ostream' : 'friend' not permitted on data declarations

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(5) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(5) : error C2061: syntax error : identifier 'ostream'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(5) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(5) : error C2805: binary 'operator <<' has too few parameters

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(6) : error C2143: syntax error : missing ';' before '&'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(6) : error C2433: 'istream' : 'friend' not permitted on data declarations

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(6) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(6) : error C2061: syntax error : identifier 'istream'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(6) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(6) : error C2805: binary 'operator >>' has too few parameters

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(12) : error C2143: syntax error : missing ';' before '&'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(12) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(12) : error C2086: 'int ostream' : redefinition

1>        d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(5) : see declaration of 'ostream'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(12) : error C2065: 'output' : undeclared identifier

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(12) : error C2059: syntax error : 'const'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(13) : error C2143: syntax error : missing ';' before '{'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(13) : error C2447: '{' : missing function header (old-style formal list?)

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : error C2143: syntax error : missing ';' before '&'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : error C2086: 'int istream' : redefinition

1>        d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(6) : see declaration of 'istream'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : error C2065: 'input' : undeclared identifier

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : error C2065: 'num' : undeclared identifier

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : error C2275: 'PhoneNumber' : illegal use of this type as an expression

1>        d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(4) : see declaration of 'PhoneNumber'

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>d:\myc++study\fig08_03\fig08_03\fig08_03.cpp(18) : fatal error C1903: unable to recover from previous error(s); stopping compilation

1>Build log was saved at "file://d:\myC++Study\fig08_03\fig08_03\Debug\BuildLog.htm"

1>fig08_03 - 27 error(s), 0 warning(s)

========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

我想这不是代码敲错了，应该是设置哪儿有问题吧。
环境是VS2005，默认安装的，没有做过设置方面的修改。之前跑过简单的C++程序也成功了。
请高手帮忙！！！