C++ Primer Plus（第五版）第10章编程题答案

2018年11月18日 1946点热度 0人点赞 1条评论

1.为复习题5描述的类提供方法定义，并编写一个小程序来演示所有的特性。

bankacc.h

#ifndef BANKACC_H_1
#define BANKACC_H_1
class Bank {
	char name[30];
	char account[7];
	double debt;
public:
	Bank();
	Bank(const char *co, const char *ac, double db = 0.0);
	~Bank();
	void show() const;
	void deposit(const double money);
	void withdrawal(const double money);
};
#endif // !BANKACC_H_1

bankacc.cpp

#include<iostream>
#include<string>
#include<cstring>
#include"bankacc.h"
using namespace std;
Bank::Bank() {
	strcpy(name, "no name");
	name[30] = '\0';
	strcpy(account, "100000");
	account[6] = '\0';
	debt = 0.0;
}
Bank::Bank(const char *co, const char *ac, double db)
{
	strncpy(name, co, 29);
	strncpy(account, ac,6);
	name[30] = '\0';
	account[6] = '\0';
	debt = db;

}
Bank::~Bank() {
	cout << "Your account has been deleted.Thank your for using our service.\n";
}
void Bank::show() const
{
	cout << "Account Name: " << name << endl;
	cout << "Account ID: " << account << endl;
	cout << "Debt: $" << debt << endl;
}
void Bank::deposit(const double money)
{
	debt += money;
	cout << "Your Debt: $" << debt << endl;
	cout << "Thank you for using deposit service.Bye~\n";

}
void Bank::withdrawal(const double money) {
	if (money <= debt)
	{
		debt -= money;
		cout << "Your Debt: $" << debt << endl;
	}
		
	else
		cout << "Error, you do not have enough money.\n";
	cout << "Thank you for using withdrawal service.Bye~\n";

}

banker.cpp

#include<iostream>
#include<string>
#include<cstring>
#include"bankacc.h"
using namespace std;

int main() {
	cout << "This is Bank example 1:" << endl;
	Bank banks1;
	banks1.show();
	cout << "After depositing..."<<endl;
	double depos1 = 3692.21;
	banks1.deposit(depos1);
	cout << "After withdrawal..." << endl;
	banks1.withdrawal(1252.63);
	cout << "#########################################" << endl;
	double money2 = 8945.32;
	Bank banks2 = Bank("Yushuai Zhang", "H6365", money2);
	banks2.show();
	cout << "After depositing..." << endl;
	double depos2 = 235.21;
	banks2.deposit(depos2);
	cout << "After withdrawal..." << endl;
	banks2.withdrawal(625.63);

	system("pause");
	return 0;
}

2.下面是一个非常简单的类定义：
（……代码省略……）
通过提供未定义的方法来完成这个类的实现。然后，编写一个使用这个类的程序，它使用了几种可能的构造函数调用（没有参数、一个参数和两个参数）以及两种显示方法。

person.cpp

#include<iostream>
#include<string>
#include<cstring>
using namespace std;
const int LIMIT = 25;
class Person {
private:
	string lname;
	char fname[LIMIT];
public:
	Person();
	Person(const string &ln, const char*fn = "Heyyou");
	void Show() const;
	void FormalShow() const;
};
Person::Person()
{
	lname = "";
	fname[0] = '\0';

}
Person::Person(const string & ln, const char *fn) {
	lname = ln;
	strncpy(fname, fn, LIMIT-1);
	fname[LIMIT - 1] = '\0';

}
void Person::Show()const {
	cout << fname << " " << lname << endl;

}

void Person::FormalShow() const {
	cout << lname << " " << fname << endl;

}
int main() {
	Person one;
	Person two("Smythecraft");
	Person three("Dimwiddy", "Sam");
	one.Show();
	cout << endl;
	one.FormalShow();
	cout << endl;
	two.FormalShow();
	cout << endl;
	three.Show();
	system("pause");
	return 0;
}

3.完成第9章的编程练习1，但要用正确的golf类声明替换那里的代码。用带合适参数的构造函数替换setgolf(golf &, const char *, int)，以提供初始值。保留setgolf()的交互版本，但要用构造函数来实现它（例如，setgolf()的代码应该获得数据，将数据传递给构造函数来创建一个临时对象，并将其赋给调用对象，即*this）。

golf.h

#ifndef GOLF_H
#define GOLF_H
class Golf {
private:
	static const int Len = 40;
	char fullname[Len];
	int handicap;
public:
	Golf(const char * name = "HHHHHH", int hc = 10);
	~Golf();
	bool setGolf();
	void sethandicap(int hc);
	void showGolf()const;
};
#endif // GOLF_H

golf.cpp

#include <iostream>
#include <cstring>
#include "golf.h"
using namespace std;

Golf::Golf(const char * name, int hc)
{
	strncpy(fullname, name, 40);
	fullname[39] = '\0';
	handicap = hc;
}

Golf::~Golf()
{
	cout << "Bye!" << endl;
}

bool Golf::setGolf()
{
	char fullname[Len];
	int handicap;

	cout << "Please input the name of the golf player: ";
	cin.get(fullname, Len); 
	if (cin)
	{
		cout << "Please input the handicap of the golf player: ";
		cin >> handicap;
		cin.get();
		*this = Golf(fullname, handicap);
		return true;
	}
	else
		return false;

}

void Golf::sethandicap(int hc)
{
	handicap = hc;
}

void Golf::showGolf()const
{
	std::cout << "hullname: " << fullname << ", \thandicap: " << handicap << std::endl;
}

main.cpp

#include <iostream>
#include "golf.h"
using namespace std;
int main()
{
	Golf one;
	Golf two;
	Golf three;

	one.showGolf();         // 默认构造函数
	two.setGolf();          // 交互版本
	two.showGolf();
	two.sethandicap(5000);  //成员函数
	two.showGolf();         //成员函数
	three.sethandicap(20);
	three.showGolf();
	system("pause");
	return 0;
}

5.考虑下面的结构声明：

struct customer {
       char fullname[35];
       double payment;
};

编写一个程序，它从栈中添加和删除customer结构（栈用Stack类声明表示）。每次customer结构被删除时，其payment的值都被加入到总数中，并报告总数。注意：应该可以直接使用Stack类而不作修改；只需修改typedef声明，使Item的类型为customer，而不是unsigned long即可。

stack.h

#pragma once
#ifndef STACK_H_
#define STACK_H_
typedef struct customer
{
	char fullname[35];
	double payment;
}CUSTOMER;

typedef customer Item;

class Stack
{
private:
	enum { MAX = 10 };    
	Item items[MAX];    
	int top;
	int total;
public:
	Stack();
	~Stack();
	bool isempty()const;
	bool isfull()const;
	bool push(const Item & item);
	bool pop(Item & item); 
};
#endif // STACK_H_

static.cpp

#include <iostream>
#include "stack.h"
using namespace std;
Stack::Stack() 
{
	top = 0;
	total = 0;
}

Stack::~Stack()
{
	cout << "Bye!\n";
}

bool Stack::isempty()const
{
	return top == 0;
}

bool Stack::isfull()const
{
	return top == MAX;
}

bool Stack::push(const Item & item)
{
	if (top < MAX)
	{
		items[top++] = item;
		return true;
	}
	else
		return false;
}

bool Stack::pop(Item & item)
{
	if (top > 0)
	{
		item = items[--top];
		total +=item.payment;
		cout << "PO#" << item.fullname << endl;
		cout << "Total = " << total << endl;
		return true;
	}
	else
		return false;
}

main.cpp

#include <iostream>
#include <cctype>
#include "stack.h"

int main()
{
	using namespace std;
	Stack st;   // create an empty stack
	char ch;
	CUSTOMER po;
	cout << "Please enter A to add a purchase order.\n"
		<< "P to process a PO,or Q to quit.\n";
	while (cin >> ch && toupper(ch) != 'Q')
	{
		while (cin.get() != '\n')
			continue;
		if (!isalpha(ch))
		{
			cout << '\a';
			continue;
		}
		switch (ch)
		{
		case 'A':
		case 'a':
			cout << "Enter a PO fullname to add:\t";
			cin.getline(po.fullname, 35);
			cout << "Enter a PO payment to add:\t";
			cin >> po.payment;
			if (st.isfull())
				cout << "stack already full\n";
			else
				st.push(po);
			break;
		case 'P':
		case 'p':if (st.isempty())
			cout << "Stack already empty\n";
				 else
					 st.pop(po);
			break;
		}
		cout << "Please enter A to add a purchase order,\n"
			<< "P to process a PO, or Q to quit.\n";
	}
	cout << "Bye\n";
	return 0;
}

6. 根据类声明，提供成员函数的定义和测试这个类的程序。

#include<iostream>
using namespace std;
class Move
{
private:
	double x;
	double y;
public:
	Move(double a = 0, double b = 0);
	void showmove()const;
	Move add(const Move &m)const;
	void reset(double a = 0, double b = 0);
};
Move::Move(double a, double b)
{
	x = a;
	y = b;
}
void Move::showmove()const {
	cout << "x= " << x << endl;
	cout << "y= " << y << endl;
}
Move Move::add(const Move & m) const {
	return Move(x + m.x, y + m.y);

}
void Move::reset(double a, double b)
{
	x = a;
	y = b;
}

int main() {
	Move move1;
	cout << "Move1:\n";
	move1.showmove();
	Move move2 = Move(2.3, 1.9);
	cout << "Move2:\n";
	move2.showmove();
	move1 = move1.add(move2);
	cout << "Move1 after adding move2:\n";
	move1.showmove();
	move1.reset();
	move2.reset();
	cout << "Reset Move1:\n"; 
	move1.showmove();
	cout << "Reset Move2:\n";
	move2.showmove();
	system("pause");
	return 0;


}

备注：

操作系统：Windows 10 x64(1803)

编译器：Microsoft Visual Studio 2015

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