c++ primer plus 习题答案(4)

p333.3

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

 class Golf{
 private:
     static const int Len = ;
     char fullname[Len];
     int handicap;
 public:
     Golf(char name[Len], int bt);
     void showgolf() const;
 };

 void setgolf(char *name, int extent, int &bt){
     cout << "enter a name\n";
     cin.get(name, extent);
     while (cin.get() != '\n')
         continue;
     cout << "enter a number\n";
     cin >> bt;
 }

 Golf::Golf(char name[Len], int bt){
     strncpy(fullname, name, Len);
     handicap = bt;
 }

 void Golf::showgolf()const{
     cout << "fullname is " << fullname << endl
         << "handicap is " << handicap;
 }

 int main(){
     Golf one = Golf("asxc", );
     int ct;
     char name[];
     setgolf(name, , ct);
     Golf two = Golf(name, ct);
     one.showgolf();
     cout << endl;
     two.showgolf();

     system("pause");
     return ;
 }

p333.4

 //头文件
 namespace SALES
 {
     class Sales{
     private:
         enum {QUARTERS=};
         double sales[QUARTERS];
         double average, max, min;
     public:
         Sales();
         Sales(const double *ar, int n);
         void showsales();
     };
 }

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

 SALES::Sales::Sales(){
     cout << "enter four number\n";
     double sum = ;
     for (int i = ; i < QUARTERS; i++){
         cin >> sales[i];
         sum += sales[i];
     }
     average = sum / QUARTERS;
     max = sales[];
     min = sales[];
     for (int i = ; i < QUARTERS; i++){
         if (max < sales[i])
             max = sales[i];
         if (min>sales[i])
             min = sales[i];
     }
 }

 SALES::Sales::Sales(const double *ar, int n){
     double sum = ;
     for (int i = ; i < n; i++){
         sales[i] = ar[i];
         sum += sales[i];
     }
     average = sum / QUARTERS;
     max = sales[];
     min = sales[];
     for (int i = ; i < QUARTERS; i++){
         if (max < sales[i])
             max = sales[i];
         if (min>sales[i])
             min = sales[i];
     }
 }

 void SALES::Sales::showsales(){
     cout << "average is " << average << endl
         << "max is " << max << endl
         << "min is " << min;
 }

 //驱动
 #include<iostream>
 #include"sales.h"
 using namespace std;

 int main(){
     using namespace SALES;
     cout << "enter four number\n";
     double ar[];
     for (int i = ; i < ; i++)
         cin >> ar[i];
     Sales market1(ar, );
     market1.showsales();
     Sales market2;
     cout << endl;
     market2.showsales();

     system("pause");
     return ;
 }

p333.5

 //头文件：
 #ifndef _STACK_H_
 #define _STACK_H_ 

 struct customer{
     char fullname[];
     double payment;
 };

 typedef customer Item;

 class Stack{
 private:
     enum{max=};
     Item items[max];
     int top;
 public:
     Stack();
     bool isfull()const;
     bool isempty()const;
     void push(const Item &);
     bool pop(const Item &);
 };

 #endif

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

 Stack::Stack(){
     top = ;
 }

 bool Stack::isfull()const{
     if (top == max)
         return true;
     else return false;
 }

 bool Stack::isempty()const{
     if (top == )
         return true;
     else return false;
 }

 void Stack::push(const Item &temp){
     if (isfull())
         cout << "the stack has already full\n";
     else items[top++] = temp;
 }

 bool Stack::pop(const Item &temp){
     if (isempty()){
         cout << "the stack has already empty\n";
         return false;
     }
     else {
         items[--top] = temp;
         return true;
     }
 }

 //驱动：
 #include<iostream>
 #include"stack.h"
 using namespace std;
 void get_customer(Item &);

 int main(){
     Item temp;
     Stack test;
     double payments=;
     cout << "enter A to push, enter P to pop or"
         <<"enter Q to quit\n";
     char ch;
     while (cin >> ch && (ch != 'Q' && ch != 'q')){
         while (cin.get() != '\n')
             continue;
         switch (ch){
         case 'A':
         case 'a':
             get_customer(temp);
             test.push(temp);
             break;
         case 'P':
         case 'p':
             if (test.pop(temp))
                 payments += temp.payment;
             cout << "now total payments is " <<
                 payments << endl;
         default:
             cout << "please enter A/P or Q\n";
         }
         cout << "enter A to push, enter P to pop or"
             << "enter Q to quit\n";
     }
     system("pause");
     return ;
 }

 void get_customer(Item &temp){
     cout << "enter a line\n";
     cin.getline(temp.fullname, );
     cout << "enter a number\n";
     cin >> temp.payment;
     cin.get();
 }