c++ Primer Plus（第六版）第十六章习题，写代码之路

c++ PRimer Plus（习题16.1)

//让用户输入回文的单词，就是那种倒着读和顺着读一样意思的//实现这个功能有很多方法，用了一种简单的方法#include<iostream>#include<string>using std::string;using std ::cout;using std::cin;using std::getline;using std::endl;bool Isplalindrome(const string &s);int main(){	string p;	cout << "Enter a plalindrome Word: ";	while (getline(cin, p)&&p != "q")	{		if (Isplalindrome(p))			cout << "Yes, " << p << " is a plalindrome word!/n";		else			cout << "Sorry,is not a plalindrome word!/n";		cout << "Think about another word: (q to exit)";		//getline(cin,p);	}	cout << "Bye!/n";}bool Isplalindrome(const string &s){	string temp = s;		//string temp(words.rbegin(), words.rend());	int j = s.size();		//用上面的反转迭代器更简单	int i=0;	for (; i <j; i++)		temp[i]=s[s.size() - i-1];			//因为string索引的问题，这里要减一个	temp[i] = '/0';	if (temp==s)		return true;	return false;}c++ Primer Plus（习题16.2)
//让用户输入回文的单词，就是那种倒着读和顺着读一样意思的//前面一道题目的升级版，客户要求的//考虑输入句子，大小写等复杂的情况//感觉思路不太好，结果没什么问题，就是饶了一点#include<iostream>#include<string>#include<cctype>				//处理大小写using std::string;using std::cout;using std::cin;using std::getline;using std::endl;bool Isplalindrome(const string &s);int main(){	string p;	cout << "Enter a plalindrome word: ";	while (getline(cin, p) && p != "q")	{		if (Isplalindrome(p))			cout << "Yes, " << p << " is a plalindrome./n";		else			cout << "Sorry,is not a plalindrome./n";		cout << "Think about another word: (q to exit)";		//getline(cin,p);	}	cout << "Bye!/n";}bool Isplalindrome(const string &s){	string temp;		//这个用于存储去掉大写，和非字母字符的string类，反转后的类				int i = 0;	int j = s.size() - 1;	for (; j>=0;j--)	{		if (isalpha(s[j]))					//判断字符是否是字母			{								//处理大小写字符			temp.push_back(tolower(s[j]));	//还是这种方法好一点			i++;		}}	//temp[i] = '/0'; string的结尾标记没有规定是'/0'这种方法不可行	string tem(temp.rbegin(), temp.rend());	if (temp == tem)		return true;	return false;}c++ Primer Plus（习题16.3)
//这题是修改程序清单16.3，改成从文件中读取单词，而不是从数组中 //书上已经有解决方案了，照着就ok.#include <iostream>  #include <fstream>  #include <vector>  #include <string>  #include <cstdlib>  #include <ctime>  #include <cctype>  const int NUM = 26;void Readword();std::vector<std::string> input;			//全局变量省的传递参数了int main(){	std::srand(std::time(0)); 	char play;	std::cout << "Will you play a word game? <Y/N> ";	std::cin >> play;	play = std::tolower(play);	Readword();	while (play=='y')	{		std::string target= input[std::rand() % NUM];		int length = target.length();		std::string attempt(length, '-');		std::string badchars;		int guesses = 6;		std::cout << "Guess my secret word. It has " << length 			<< " letters, and you guess/n" << "one letter at a time. You get " 			<< guesses << " wrong guesses./n";		std::cout << "Your word: " << attempt << std::endl;		while (guesses > 0 && attempt != target)		{			char letter;			std::cout << "Guess a letter: ";			std::cin >> letter;			if ((badchars.find(letter) != std::string::npos) //nops是string中的最大存储字符数				|| (attempt.find(letter)!= std::string::npos))			{				std::cout << "You already guessed that. Try again./n";				continue;			}			int loc = target.find(letter);			//记录找到字符的位置			if (loc == std::string::npos)			{				std::cout << "Oh, bad guess!/n";				--guesses;				badchars +=letter;					//记录到错误的那里			}			else			{				std::cout << "Good guess!/n";				attempt[loc] =letter;		//显示猜对的字符				loc = target.find(letter, loc + 1);				while (loc != std::string::npos)	//显示这个单词后面相同的字符				{					attempt[loc] =letter;					loc = target.find(letter, loc + 1);				}			}			std::cout << "Your word: " << attempt << std::endl;			if (attempt != target)			{				if (badchars.length() > 0)					std::cout << "Bad choices: " << badchars << std::endl;				std::cout << guesses << " bad guesses left/n";			}		}		if (guesses > 0)			std::cout << "That's right/n";		else			std::cout << "Sorry, the word is " << target << "./n";		std::cout << "Will you play another? <Y/N> ";		std::cin >> play;		play = tolower(play);	}	std::cout << "Bye!/n";	return 0;}void Readword(){	std::ifstream fin;	fin.open("data.txt");	if(!fin.is_open())	{		std::cout << "Open file data.txt error!/n";		exit(EXIT_FAILURE);	}	std::string s;				//存储读取的单词	while (!fin.eof())	{		fin>>s;		input.push_back(s);			//动态增加input的成员数量	}	fin.close();}c++ Primer Plus（习题16.4)
//这题是熟悉stl特性，编写一个函数接受一个数组和元数个数//对数组进行排序，删除重复的值，并返回最终的元素个数//考虑到压缩元素，可以使用list模板类，书上的unique()函数也是一种提示#include<iostream>#include<list>							//list模板，双向链表#include<algorithm>						//迭代器std::list<long>f;int reduce(long ar[], int i);void outlong(long n) { std::cout << n << " "; }int main(){	using std::cout;	long test[12] = { 40,51,57,89,87,85,40,40,51,64,52,0 };	int result;	result = reduce(test, 12);	cout << "Source array: /n";	for (long x : test)					//基于范围的for循环			cout << x << " ";	cout << "/nThe mount: " << 12;	std::cout << "/nAfter sort and remove, the number is "<<result<<std::endl;	cout << "After that: /n";	std::for_each(f.begin(), f.end(), outlong);	std::cout << "Bye!/n";	return 0;}int reduce(long ar[], int i)			//使用迭代器将非常其简单，不过要会choose{	f.insert(f.begin(),ar, ar + i);	f.sort();						//排序	f.unique();						//压缩相同的元素	return f.size();}c++ Primer Plus（习题16.5)
//这题是上一题的泛型，可以不依赖于特定的数组类型//这就是迭代器的终极奥义，独立于类型#include<iostream>#include<algorithm>#include<string>#include<list>	template<class T>int reduce(T ar[], int n);template<class T>void outlong(T n) { std::cout << n << " "; }int main(){	using std::cout;	cout << "Test a function,accept a type array and longth,return after reduce same elemet"		"mount." << std::endl;	long test[12] = { 40,51,57,89,87,85,40,40,51,64,52,0 };	int result;	result = reduce(test, 12);	cout << result<<std::endl;std::string tests[5] = { "i","m a C","+","+","student." };	result = reduce(tests, 5);	cout << result<<std::endl;}template<class T>int reduce(T ar[], int n){	std::list<T>f;	f.insert(f.begin(), ar, ar + n);	f.sort();	f.unique();	std::cout << "After reduce and sort:/n";	std::for_each(f.begin(), f.end(), outlong<T>);	std::cout << std::endl;	return f.size();	}c++ Primer Plus（习题16.6)
//改写程序清单12.12就是那个排队买东西的，在c primer中也有//使用stl queue 有高级的函数辅助加上一些queue 的stl功能，//很容易实现,毕竟是标准的，我们自己做的功能没那么强大#include <iostream>  #include <cstdlib>  #include <ctime>  #include <queue>class Customer{private:	long arrive;	int processtime;public:	Customer() { arrive = processtime = 0; }	void set(long when) 	{		processtime = std::rand() % 3 + 1;		arrive = when;	}	long when()const { return arrive; }	int ptime()const { return processtime; }};typedef Customer Item;const int MIN_PER_HR = 60;bool newcustomer(double x);int main(){	using namespace std;	srand(time(0));	cout << "Case Study: Bank of Heather Automatic Teller/n";	cout << "Enter maximum size of queue: ";		//最大的排队人数	int qs;	cin >> qs;	queue <Item>line;								//queue本人没看到指定队列数的构造函数	cout << "Enter the number of simulation hours: ";	//测试的时间	int hours;	cin >> hours;	long cyclelimit = MIN_PER_HR*hours;	cout << "Enter the average number of cunstomers per hour: ";	//每小时的额客户数	double perhour;	cin >> perhour;	double min_per_cust;	min_per_cust = MIN_PER_HR / perhour;				//记录总的分钟数	Item temp;	long turnaways = 0;									//拒绝人数	long customers = 0;									//来的人数	long served = 0;									//服务人数	long sum_line = 0;									//队列的长度	int wait_time = 0;									//取款机空闲的等待时间		long line_wait = 0;									//队列的总等待时间	for (long cycle = 0; cycle < cyclelimit; cycle++)	{		if (newcustomer(min_per_cust))		{			if (line.size()==qs)						//检查队列的长度是否等于最大排队人数				turnaways++;			else 			{				customers++;				temp.set(cycle);				line.push(temp);							//enqueue和push同样的方法			}		}		if (wait_time <= 0 && !line.empty())		{			line.pop();								//弹出，不需要item参数			wait_time = temp.ptime();				line_wait += cycle - temp.when();			served++;		}		if (wait_time > 0)			wait_time--;		sum_line += (line.size()) / 2;	}	if (customers > 0) {		cout << "customers accepted: " << customers << endl;		cout << "  customers served: " << served << endl;		cout << "        turnaways: " << turnaways << endl;		cout << "average queue size: ";		cout.precision(2);		cout.setf(ios_base::fixed, ios_base::floatfield);		cout << (double)sum_line / cyclelimit << endl;		cout << "average wait time: " << (double)line_wait / served << " minutes/n";	}	else		cout << "No customers!/n";	cout << "Done!/n";	return 0;}bool newcustomer(double x){	return (rand()*x / RAND_MAX < 1);}c++ Primer Plus（习题16.7)
//一个彩票卡的游戏，本人没听说过，//也是设计一个函数，要求使用vector容器//额，程序每次运行获取的值都一样，这要是真是中奖的程序，等着骂吧#include<iostream>#include<vector>#include<algorithm>using namespace std;vector<int> Lotto(int count, int ccount);	//返回一个包含vector										//从第一个参数随机选择第二个参数数量值的对象int main(){	cout << "This is a Lottery card Test program."		"To test a funtion Lotto: /n";	vector<int>winners;	int numb, times;	cout << "Enter a draw range: ";	cin >> numb;	cout << "How many times your draw less than: ";	cin >> times;	winners = Lotto(numb,times);	cout<< "The winners Lottery card winning number is:/n";	for (auto m = winners.begin(); m != winners.end(); m++)    //用迭代器的方式输出容器对象的值	{		cout<< *m << endl;	}	cout << "Good lucky!/n";	cout << "Test complete!/n";	return 0;}vector<int> Lotto(int count, int ccount){	vector<int>pvalue(count);				//用来记录可能值,用了指定元素个数的f方法	vector<int>value;						//用于返回	for (int i = 0; i < count; i++)		pvalue[i] = i + 1;	for (int i = 0; i < ccount; i++)				//打乱ccount指定的次数，每次取第一个值存入数组	{		random_shuffle(pvalue.begin(), pvalue.end());		value.push_back(pvalue[0]);	}	return value;}c++ Primer Plus（习题16.8)
//两个朋友认识的人的名字，用容器存储//合并两个人中相同的元素，保存到第三个容器中//考虑采用set关联容器#include<iostream>#include<string>#include<set>#include<algorithm>#include<iterator>				//迭代器的头文件int main(){	using namespace std;	ostream_iterator<string, char>out(cout, " ");			//输出迭代器	string Mat[5] = { "Joly","Jack","Zoe","Jay,Zou","X" };	//直接用这个来初始化了	string Pat[4] = { "Joly","Emil","X","Lai Mei" };	set<string>A(Mat, Mat + 5);			//第一个容器,set容器自动排序，大家都知道	cout << "Mat's friends:/n";	copy(A.begin(), A.end(), out);		//STL函数，复制到输出流迭代器	cout << endl;						//说白了，就是显示容器内容	set<string>B(Pat, Pat + 4);	cout << "Pat's friends:/n";	copy(B.begin(), B.end(), out);	cout << endl;	set<string>C;	set_union(A.begin(), A.end(), B.begin(), B.end(), 		insert_iterator<set<string>>(C, C.begin()));		//AB集合，用了一个插入迭代器	cout << "Friends they have:/n";	copy(C.begin(), C.end(), out);	cout << endl;	return 0;}c++ Primer Plus（习题16.9)
//这是作者的一个假设，在我们生活中也有很多这样的假设//他的思路是在数组中排序元素，然后复制到链表中（因为链表排序是在很麻烦）//借用中间容器实现排序功能的实现，下面就是测试时间#include<iostream>#include<vector>#include<list>#include<algorithm>#include<iterator>#include<ctime>					//提供时间函数const int Num=1000000;			//这个要足够大void outint(int n) { std::cout << n << " "; }int main(){	using namespace std;	vector<int>vi0(Num);				//指定个数的初始化	for (int i=0; i < Num; i++)		vi0[i]=rand()%100 + 1;	cout << "Hello,this program set to accumulate time between STL sort method "		"for vector object,and list sort methods./n";	cout << "Number of elements is " << Num << endl;	vector<int>vi;	vi = vi0;										//调用vector的赋值运算符	list<int>li(Num);								//指定个数的初始化	copy(vi0.begin(), vi0.end(), li.begin());		//不同容器之间的数据复制	//计算三种方法的时间，方法一，使用使用STL算法对vi进行排序	clock_t start = clock();	sort(vi.begin(), vi.end());	clock_t end = clock();	cout << "Frist method,using STL sort time " << (double)(end - start) / CLOCKS_PER_SEC << " s./n";	//第二次测试	clock_t start_2= clock();	li.sort();	clock_t end_2= clock();	cout << "Second method,using list sort time " << (double)(end_2 - start_2) / CLOCKS_PER_SEC << " s./n";	//第三次测试	copy(vi0.begin(), vi0.end(), li.begin());		//重置li链表	clock_t start_3 = clock();	copy(li.begin(), li.end(), vi.begin());			//把list的值复制到vi容器	sort(vi.begin(), vi.end());						//排序	copy(vi.begin(), vi.end(), li.begin());	clock_t end_3 = clock();	cout << "Third method,using other sort time " << (double)(end_3 - start_3) / CLOCKS_PER_SEC << " s./n";	cout << "Now,you can see,/nwhen list container count become big,sortting them is too long."		"/nSo,make right choice to compelete a function./n";	return 0;}c++ Primer Plus（习题16.10)
//又是修改程序的题目，这最后的习题涉及到智能指针//然后我们要做的就是满足客户的额要求,升级我们的程序//不知道加了哪个头文件导致cout不明确//这题的思路是书上的方案，如果自己做的话可以想排序字符串那样//只使用指针数组排序，对指针进行排序#include<iostream>#include<string>#include<vector>#include<algorithm>				//提供一些STL方法#include<memory>				//智能指针头文件struct Review					//结构是一种默认为公有的类{	std::string title;	int rating;	double price;				//增加的成员，书价格};using namespace std;		//书上也是按引用传递指针的意义非凡，其实不还是指针，没设呢么区别bool Operator<(shared_ptr<Review>r1, shared_ptr<Review>r2);//按字母排序的bool woreThan(shared_ptr<Review>r1, shared_ptr<Review>r2);	//评分排序的bool expensivethen(shared_ptr<Review>r1, shared_ptr<Review>r2);	//价格排序的bool FillReview(Review*rr);void ShowReview(shared_ptr<Review>rr);			//有点特别，书上的用法void Showmenu();int main(){	Review temp;	vector<shared_ptr<Review>>pr;	while (FillReview(&temp))		pr.push_back(shared_ptr<Review>(new Review(temp)));	//没认真看书，这个初始化想了好久好久	vector<shared_ptr<Review>>tem(pr);		//用vector自带的初始化,是一个按名称排序的vector	sort(tem.begin(), tem.end());			//创建按指针排序的<运算符，全排序	//按评分排序的	vector<shared_ptr<Review>>tem2(pr);	sort(tem2.begin(), tem2.end(), woreThan);		//调用函数进行排序，完整弱排序	//按价格排序	vector<shared_ptr<Review>>tem3(pr);	sort(tem3.begin(), tem3.end(), expensivethen);	if (pr.size() > 0)	{		std::cout<< "Thank you,You entered the following "			<< pr.size() << " ratings./n";		Showmenu();		char choose;		cin >> choose;		while (choose != 'q')		{			switch (choose)			{					//天真的我竟然在后面加&这个			case 'a':for_each(pr.begin(),pr.end(), ShowReview); break;			case'b': for_each(tem.begin(),tem.end(), ShowReview); break;			case'c':for_each(tem2.begin(), tem2.end(), ShowReview); break;			case'd':for_each(tem2.rbegin(), tem2.rend(), ShowReview); break;			case 'e':for_each(tem3.begin(), tem3.end(), ShowReview); break;			case'f':for_each(tem3.rbegin(), tem3.rend(), ShowReview); break;			case 'q':break;			default: std::cout << "Error choose,choose again:/n";				break;			}			Showmenu();			cin >> choose;		}	}	else		std::cout << "No data!/n";	std::cout << "Bye!/n";	return 0;}bool operator<(shared_ptr<Review>r1, shared_ptr<Review>r2)		{	if (r1->title < r2->title)		return true;	else if (r1->title == r2->title&&r1->rating < r2->rating)		return true;		//这里不想太麻烦，就选择评分为优先排序项目	else		return false;}bool woreThan(shared_ptr<Review>r1, shared_ptr<Review>r2)  //按评分升序{	if (r1->rating<r2->rating)		return true;	else		return false;}bool expensivethen(shared_ptr<Review>r1, shared_ptr<Review>r2) //按价格升序{	if (r1->price < r2->price)		return true;	else		return false;}bool FillReview(Review*rr){	std::cout << "Enter book title(quit to quit): ";	std::getline(std::cin, rr->title);	if (rr->title == "quit")		return false;	std::cout << "Enter book rating: ";	std::cin >> rr->rating;	if (!std::cin)		return false;					//检查错误输入	std::cout << "Enter book price(unit:yuan): ";	std::cin >> rr->price;	if (!std::cin)		return false;	while (std::cin.get() != '/n')		continue;	return true;}void ShowReview(shared_ptr<Review>rr){	std::cout << rr->title<< "/t/t/t/t/t" << rr->rating << "/t $ " << rr->price 		<< "/tyuan./n";}void Showmenu(){	std::cout << "Make a choose to display them: /n"		"a) Display by original order.            b) Display by alphabetic order./n"		"c) Display by rating ascending order.     d) Display by rating descending order./n"		"e) Display by price ascending order.      f) Display by price descending order./n"		"q) quit./n";}