c++ primer plus 习题答案(5)

p333.7

 #include<iostream>
 #include<cstring>
 #include<cstdlib>
 using namespace std;

 class Plorg{
 private:
     char fullname[];
     int CI;
 public:
     Plorg(char *ar = "Plorga", int ct = );
     void index();
     void show()const;
 };

 Plorg::Plorg(char *ar, int ct){
     strcpy(fullname, ar);
     CI = ct;
 }

 void Plorg::index(){
     cout << "enter a number of CI\n";
     cin >> CI;
 }

 void Plorg::show()const{
     cout << "fullname is " << this->fullname <<
         " CI is " << (*this).CI << endl;
 }

 int main(){
     Plorg test1;
     cout << "enter a line\n";
     char ar[];
     int ct;
     cin.getline(ar, );
     cout << "enter a number\n";
     cin >> ct;
     cin.get();
     Plorg test2(ar, ct);
     test1.show();
     cout << endl;
     test2.show();
     test1.index();
     cout << endl;
     test1.show();

     system("pause");
     return ;
 }

p375.5

 //头文件：
 #include<iostream>

 #ifndef _STONEWT_H
 #define _STONEWT_H
 class Stonewt{
 private:
     static const int lbs_per_stn = ;
     int stone;
     double pds_left;
     double pounds;
     char mode;
 public:
     Stonewt();
     Stonewt(double, char ch='P');
     Stonewt(int, double, char ch='P');
     ~Stonewt();
     void set(Stonewt &);
     void mode_invert(char);
     Stonewt operator+(const Stonewt & a)const
     {return Stonewt(pounds + a.pounds); }
     friend Stonewt operator-(const Stonewt &, const Stonewt &);
     friend Stonewt operator*(double n, const Stonewt &);
     friend std::ostream & operator<<(std::ostream &, const Stonewt &);
 };

 #endif

 //方法：
 #include<iostream>
 #include"stack.h"
 using std::cout;
 using std::cin;
 using std::endl;

 Stonewt::Stonewt(){
     pds_left = pounds = stone = ;
     mode = 'P';
 }

 Stonewt::Stonewt(double a, char ch){
     pounds = a;
     stone = int(a / lbs_per_stn);
     pds_left = pounds - stone*lbs_per_stn;
     mode = ch;
 }

 Stonewt::Stonewt(int a, double b, char ch){
     pounds = a*lbs_per_stn + b;
     stone = a + int(b / lbs_per_stn);
     pds_left = pounds - stone*lbs_per_stn;
     mode = ch;
 }

 void Stonewt::set(Stonewt &a){
     cout << "enter stone\n";
     cin >> a.stone;
     cout << "enter pounds\n";
     cin >> a.pds_left;
     a.pounds = a.stone*lbs_per_stn + a.pds_left;
     cout << "enter a mode that you want to choice\n";
     cin >> a.mode;
 }

 Stonewt::~Stonewt(){

 }

 Stonewt operator-(const Stonewt &a, const Stonewt &b){
     Stonewt sum;
     sum = a + b;
     return sum;
 }

 Stonewt operator*(double n, const Stonewt &a){
     return Stonewt(n*a.pounds);
 }

 std::ostream & operator<<(std::ostream &os, const Stonewt &t){
     if (t.mode == 'P')
         cout << "pounds is " << t.pounds;
     else if (t.mode == 'S')
         cout << "stone is " << t.stone << " pds_left is " << t.pds_left << endl;
     else cout << "wrong choices\n";
     return os;
 }

 //驱动：
 #include<iostream>
 #include<cstdlib>
 #include"stack.h"
 using std::cout;
 using std::endl;

 int main(){
     Stonewt ct(54.6, 'S');
     Stonewt bt(, 56.3, 'P');
     Stonewt at;
     Stonewt dt = bt + ct;
     Stonewt ft = bt - ct;
     int n = ;
     Stonewt gt = n*bt;
     cout << ct << endl << bt << endl
         << dt << endl << ft << endl
         << gt << endl<<at;

     system("pause");
     return ;
 }

p375.7

 //头文件：
 #include<iostream>

 #ifndef _COMPLEX_H
 #define _COMPLEX_H

 using std::ostream;
 using std::istream;

 namespace COMPLEX{
     class Complex{
     private:
         double real;
         double imaginary;
     public:
         Complex();
         Complex(double, double);
         Complex operator+(const Complex &);
         Complex operator-(const Complex &);
         friend Complex operator*(const Complex &, const Complex &);
         friend Complex operator*(const Complex &, const double);
         friend Complex operator~(const Complex &);
         friend ostream & operator<<(ostream &, const Complex &);
         friend istream & operator>>(istream &, Complex &);
     };
 }

 #endif

 //方法：
 #include<iostream>
 using namespace std;
 #include"stack.h"

 namespace COMPLEX{
     Complex::Complex(){
         real = imaginary = ;
     }

     Complex::Complex(double a, double b){
         real = a;
         imaginary = b;
     }

     Complex Complex::operator+(const Complex &a){
         return Complex(real + a.real, imaginary + a.imaginary);
     }

     Complex Complex::operator-(const Complex &a){
         return Complex(real - a.real, imaginary - a.imaginary);
     }

     Complex operator*(const Complex &a, const Complex &b){
         return Complex(a.real*b.real - a.imaginary*b.imaginary, a.real*b.imaginary + a.imaginary*b.real);
     }

     Complex operator*(const Complex &a, const double b){
         return Complex(a.real*b, a.imaginary*b);
     }

     Complex operator~(const Complex &a){
         return Complex(a.real, -a.imaginary);
     }

     ostream & operator<<(ostream &os, const Complex &b){
         cout << "(" << b.real << ", " << b.imaginary << "i)";
         return os;
     }

     istream & operator>>(istream &is, Complex &a){
         if (is >> a.real){
             is >> a.imaginary;
             cout << "real: " << a.real << endl;
             cout << "imaginary: " << a.imaginary << endl;
         }
         return is;
     }
 }

 //驱动：
 #include<iostream>
 using namespace std;
 #include"stack.h"
 using namespace COMPLEX;

 int main(){
     Complex a(3.0, 4.0);
     Complex c;
     cout << "enter a complex number(q to quit)\n";
     while (cin>>c){
         cout << "c is " << c << endl;
         cout << "complex conjugate is " << ~c << endl;
         cout << "a is " << a << endl;
         cout << "a+c  is " << a + c << endl;
         cout << "a-c is " << a - c << endl;
         cout << "a*c is " << a*c << endl;
         cout << "2*c is " << c* << endl;
         cout << "enter a complex number(q to quit)\n";
     }
     cout << "Done!\n";
     system("pause");
     return ;
 }