1.
play.cpp
#include <iostream>
using namespace std;
#include <string>
bool IsHui(const string &str);
int main()
{
cout << "Enter input(empty input to quit): ";
string input;
getline(cin, input);
while (cin && input.size()>0)
{
if(IsHui(input))
cout << "Yes.\n";
else
cout << "No.\n";
cout << "Enter input(empty input to quit): ";
getline(cin, input);
}
cout << "End.\n";
return 0;
}
bool IsHui(const string &str)
{
string f(str.rbegin(), str.rend());//字符串反轉
return (str == f);
}
2.
本題要求在考慮空格、大小寫和標點符號的情況下來測試迴文，整體程序框架可以與上一題完全一樣，只需要修改判斷是否是迴文的bool函數。
在判斷是否是迴文之前，我們必須把空格和標點符號去掉，然後把大小寫歸一化才行。對於去掉空格和標點符號，最簡單的方法是調用cctype庫中的erase()函數，該函數會刪去指定的字符，那麼我們可以使用isalpha()函數來判斷是否是字母，如果不是字母，即空格或者各式各樣的標點符號，則調用erase()函數將其刪去。對於大小寫的歸一化，我們可以統一到一種格式上，比如按照題目中舉的例子，就是統一都格式化成小寫，那麼就是使用tolower()函數。
#include <iostream>
using namespace std;
#include <string>
#include <cctype>
bool IsHui(const string &str);
int main()
{
cout << "Enter input(empty input to quit): ";
string input;
getline(cin, input);
while (cin && input.size()>0)
{
if(IsHui(input))
cout << "Yes.\n";
else
cout << "No.\n";
cout << "Enter input(empty input to quit): ";
getline(cin, input);
}
cout << "End.\n";
return 0;
}
bool IsHui(const string &str)
{
string str_test = str;//必須有
for(auto i = str_test.begin(); i != str_test.end();) //i是str_test各元素所在的位置,*i是元素
{
if(!isalpha(*i))
{
i = str_test.erase(i);//該位置的元素去掉
continue;
}
else
{
*i = tolower(*i);
i++;
}
}
string f(str_test.rbegin(), str_test.rend());
return (str_test == f);
}
3.
play.cpp
//改自清單16.3
#include <iostream>
using namespace std;
#include <cctype>
#include <cstdlib>
#include <ctime>
#include <string>
#include <vector>
#include <fstream>
int main()
{
const string filename = "wordlist.txt";
vector<string> wordlist;
ifstream fin;
fin.open(filename.c_str());
if(fin.is_open() == false)
{
cerr << "Can't open file.Bye.\n";
exit(EXIT_FAILURE);
}
string temp;
while (fin >> temp)
wordlist.push_back(temp);
//以下按清單16.3
const int NUM = wordlist.size();
srand(time(0));
char play;
cout << "Will you play a word game? <y/n>";
cin >> play;
play = tolower(play);
while (play == 'y')
{
string target = wordlist[rand() % NUM];
int length = target.length();
string attempt(length, '-');
string badchars;
int guesses = 6;
cout << "Guess my secret word. It has " << length
<< " letters, and you guess\n"
<< "one letter at a time. You get " << guesses
<< " wrong guesses.\n";
cout << "Your word: " << attempt << endl;
while (guesses > 0 && attempt != target)
{
char letter;
cout << "Guess a letter: ";
cin >> letter;
if(badchars.find(letter) != string::npos
|| attempt.find(letter) != string::npos)
{
cout << "You already guessed that. Try again.\n";
continue;
}
int loc = target.find(letter);
if(loc == string::npos)
{
cout << "Oh, bad guess!\n";
--guesses;
badchars += letter;
}
else
{
cout << "Good guess!\n";
attempt[loc] = letter;
loc = target.find(letter, loc + 1);
while (loc != string::npos)
{
attempt[loc] = letter;
loc = target.find(letter, loc + 1);
}
}
cout << "Your word: " << attempt << endl;
if(attempt != target)
{
if(badchars.length() > 0)
cout << "Bad choices: " << badchars << endl;
cout << guesses << " bad guesses left\n";
}
}
if(guesses > 0)
cout << "That's right!\n";
else
cout << "Sorry, the word is " << target << ".\n";
cout << "Will you play another? <y/n>";
cin >> play;
play = tolower(play);
}
cout << "Bye\n";
return 0;
}
4.
play.cpp
//排序，去重
#include <iostream>
using namespace std;
#include <algorithm>
int reduce(long ar[], int n);
int main()
{
long arr_test[10] = {156, 124, 23, 43, 35, 23, 124, 199, 210, 56};
cout << "Original array:\n";
for(int i = 0; i < 10; i++)
cout << arr_test[i] << " ";
cout << endl;
int newsize = reduce(arr_test, 10);//返回縮減後數組中的元素數目
cout << "Newsize: " << newsize << endl;
cout << "After reduction, array:\n";
for(int i = 0; i < newsize; i++)
cout << arr_test[i] << " ";
cout << endl;
return 0;
}
int reduce(long ar[], int n)
{
sort(ar, ar + n);//排序
long * arr_new;
arr_new = unique(ar, ar + n);//去重
//用unique()函數返回結果區間結尾的特點，將該結尾指針地址賦給一個long指針，將該地址減去實參的數組名地址，即是縮減後的元素數目
return arr_new - ar;
}
5.
本題是編寫練習4的延伸，要求我們把原本的long數組修改爲模板類，然後分別使用long實例和string實例來驗證。
我們依然沿用編程練習4的思路和程序框架，首先把reduce()函數的實參進行修改，ar[]現在不再是long數組了，而是模板類T的數組，那麼對應的在函數內部聲明的new_ar指針的類型也就相應變成T模板類。
play.cpp
//改自第4題
#include <iostream>
using namespace std;
#include <algorithm>
template <class T>
int reduce(T ar[], int n);
int main()
{
long arr_test[10] = {156, 124, 23, 43, 35, 23, 124, 199, 210, 56};
cout << "Original array:\n";
for(int i = 0; i < 10; i++)
cout << arr_test[i] << " ";
cout << endl;
int newsize = reduce(arr_test, 10);//返回縮減後數組中的元素數目
cout << "Newsize: " << newsize << endl;
cout << "After reduction, the long array:\n";
for(int i = 0; i < newsize; i++)
cout << arr_test[i] << " ";
cout << endl;
cout << "The second test array: \n";
string arr_test2[10] = {"hah", "china", "play", "end", "hah", "play", "speak", "play", "zero", "apple"};
cout << "Original array:\n";
for(int i = 0; i < 10; i++)
cout << arr_test2[i] << " ";
cout << endl;
int newsize2 = reduce(arr_test2, 10);//返回縮減後數組中的元素數目
cout << "Newsize: " << newsize2 << endl;
cout << "After reduction, the long array:\n";
for(int i = 0; i < newsize2; i++)
cout << arr_test2[i] << " ";
cout << endl;
return 0;
}
template <class T>
int reduce(T ar[], int n)
{
sort(ar, ar + n);//排序
T * arr_new;
arr_new = unique(ar, ar + n);//去重
//用unique()函數返回結果區間結尾的特點，將該結尾指針地址賦給一個long指針，將該地址減去實參的數組名地址，即是縮減後的元素數目
return arr_new - ar;
}
6.
本題要求我們對程序清單12.12進行修改，使用STL queue模板類來代替Queue類。我們可以沿用程序清單12.12的程序框架，把"queue.h"換成<queue>即可。同時將queue.h內聲明的Customer類放在同一個文件中聲明和定義，放棄Queue類，轉而使用queue<Customer>模板類來代替。
所以我們只需要把main()函數裏面的Queue類聲明改爲queue<Customer>類聲明即可.
play.cpp
//改自清單12.12
#include <iostream>
using namespace std;
#include <queue>
#include <cstdlib>
#include <ctime>
class Customer
{
long arrive;
int processtime;
public:
Customer() {arrive = processtime = 0;}
void set(long when) {processtime = rand()%3 + 1; arrive = when;}
long when() const { return arrive;}
int ptime() const { return processtime;}
};
const int MIN_PER_HR = 60;
bool newcustomer(double x);
int main()
{
srand(time(0));
cout << "Case Study: Bank of Heather Automatic Teller\n";
cout << "Enter maximum size of queue: ";
int qs;
cin >> qs;
queue<Customer> line;
cout << "Enter the number of simulation hours: ";
int hours;
cin >> hours;
long cyclelimit = MIN_PER_HR * hours;
cout << "Enter the average number of customers per hour: ";
double perhour;
cin >> perhour;
double min_per_cust;
min_per_cust = MIN_PER_HR / perhour;
Customer temp;
long turnaways = 0;
long customers = 0;
long served = 0;
long sum_line = 0;
int wait_time = 0;
long line_wait = 0;
for(int cycle = 0; cycle < cyclelimit; cycle++)
{
if(newcustomer(min_per_cust))
{
if(qs == line.size())
turnaways++;
else
{
customers++;
temp.set(cycle);
line.push(temp);
}
}
if(wait_time <= 0 && !line.empty())
{
temp = line.front();
wait_time = temp.ptime();
line_wait += cycle - temp.when();
served++;
line.pop();
}
if(wait_time > 0)
wait_time--;
sum_line += line.size();
}
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);
}
7.
play.cpp
#include <iostream>
using namespace std;
#include <vector>
#include <algorithm>
vector<int> Lotto(int cnum, int rnum);
int main()
{
vector<int> winners;
winners = Lotto(51, 6);
cout << "Winner's number:\n";
for(auto i = winners.begin(); i != winners.end(); i++)
cout << *i << " ";
cout << endl;
return 0;
}
vector<int> Lotto(int cnum, int rnum)
{
vector<int> ticket(cnum);
for(int i = 0; i < cnum; i++)
ticket[i] = i + 1;
random_shuffle(ticket.begin(), ticket.end());
vector<int> choose(rnum);
for(int i = 0; i < rnum; i++)
choose[i] = ticket[i];
sort(choose.begin(), choose.end());
return choose;
}
8.
play.cpp
#include <iostream>
using namespace std;
#include <vector>
#include <string>
#include <algorithm>
int main()
{
vector<string> mat_f, pat_f, total_f;//3個容器
cout << "Enter Mat's friends(empty line to quit):\n";
string temp;
while (getline(cin, temp))
{
mat_f.push_back(temp);
total_f.push_back(temp);
if(temp[0] == '\0')
break;
}
cout << "The following are Mat's friends:\n";
sort(mat_f.begin(), mat_f.end());
for(auto i = mat_f.begin(); i != mat_f.end(); i++)
cout << *i << endl;
cout << endl << endl;
cout << "Enter Pat's friends(empty line to quit):\n";
while (getline(cin, temp))
{
pat_f.push_back(temp);
total_f.push_back(temp);
if(temp[0] == '\0')
break;
}
cout << "The following are Pat's friends:\n";
sort(pat_f.begin(), pat_f.end());
for(auto i = pat_f.begin(); i != pat_f.end(); i++)
cout << *i << endl;
cout << endl << endl;
sort(total_f.begin(), total_f.end());
unique(total_f.begin(), total_f.end());
cout << "There are " << total_f.size() << " friends to be invited in total:\n";
for(auto i = total_f.begin(); i != total_f.end(); i++)
cout << *i << endl;
cout << endl << endl;
return 0;
}
9.
play.cpp
#include <iostream>
using namespace std;
#include <algorithm>
#include <ctime>
#include <vector>
#include <list>
#include <string>
const int NUM = 10000000;
int main()
{
cout << "-------begin--------" << endl;
srand(time(0));
vector<int> vi0(NUM);
for(int i = 0; i < NUM; i++)
vi0[i] = rand();
vector<int> vi(vi0);//創建vector<int>對象vi和list<int>對象li，它們的長度都和初始值與vi0相同
list<int> li(vi0.begin(), vi0.end());
cout << "Measure the sort() algorithm's running time for vector<int>:\n";
clock_t vector_start = clock();
sort(vi.begin(), vi.end());
clock_t vector_end = clock();
cout << "The time is " << (double)(vector_end - vector_start) / CLOCKS_PER_SEC << "s.\n";
cout << "Measure the sort() algorithm's running time for list<int>:\n";
clock_t list_start = clock();
li.sort();
clock_t list_end = clock();
cout << "The time is " << (double)(list_end - list_start) / CLOCKS_PER_SEC << "s.\n";
cout << "Measure the copy() and sort() algorithm's running time:\n";
copy(vi0.begin(), vi0.end(), li.begin());//li重置爲排序的vi0的內容
clock_t copy_start = clock();
copy(li.begin(), li.end(), vi.begin());//將li的內容複製到vi中
sort(vi.begin(), vi.end());//對vi進行排序
copy(vi.begin(), vi.end(), li.begin());//並將結果複製到li中
clock_t copy_end = clock();
cout << "The time is " << (double)(copy_end - copy_start) / CLOCKS_PER_SEC << "s.\n";
return 0;
}
10.
play.cpp
//改自清單16.9
#include <iostream>
using namespace std;
#include <algorithm>
#include <vector>
#include <string>
struct Review
{
string title;
int rating;
double price;
};
//按題，不使用vector<Review>來存儲輸入，而使用vector<shared_ptr<Review>>
bool operator <(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2);
//添加betterthan(),expensivethan(),cheapthan()函數，來讓用戶選擇按評級降序顯示，按價格降序顯示，按價格升序顯示
bool worsethan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2);
bool betterthan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2);
bool expensivethan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2);
bool cheapthan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2);
bool FillReview(Review &rr);
void ShowReview(const shared_ptr<Review> &rr);
int main()
{
vector<shared_ptr<Review>> books;
Review temp;
while (FillReview(temp))
{
shared_ptr<Review> newtemp(new Review(temp));
books.push_back(newtemp);
}
if(books.size() > 0)
{
cout << "Thank you. You entered the following "
<< books.size() << " ratings:\n"
<< "Rating\tBook\n";
for_each(books.begin(), books.end(), ShowReview);
cout << "Please choose a type to show(0 for original order, 1 for alphabet order, 2 for rating ascend order, \n3 for rating discend order, 4 for price ascend order, 5 for price discend order, q for quit): ";
int input;
while (cin >> input)
{
switch (input)
{
case 0:
break;
case 1:
sort(books.begin(), books.end());
break;
case 2:
sort(books.begin(), books.end(), worsethan);
break;
case 3:
sort(books.begin(), books.end(), betterthan);
break;
case 4:
sort(books.begin(), books.end(), cheapthan);
break;
case 5:
sort(books.begin(), books.end(), expensivethan);
break;
default:
break;
}
for_each(books.begin(), books.end(), ShowReview);
cout << "Please choose a type to show(0 for original order, 1 for alphabet order, 2 for rating ascend order, \n3 for rating discend order, 4 for price ascend order, 5 for price discend order, q for quit): ";
}
}
else
cout << "No entries. ";
cout << "Bye.\n";
return 0;
}
bool operator <(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2)
{
if(r1->title < r2->title)
return true;
else if (r1->title == r2->title && r1->rating < r2->rating)
return true;
else
return false;
}
bool worsethan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2)
{
if(r1->rating < r2->rating)
return true;
else
return false;
}
bool betterthan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2)
{
if(r1->rating > r2->rating)
return true;
else
return false;
}
bool expensivethan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2)
{
if(r1->price > r2->price)
return true;
else
return false;
}
bool cheapthan(const shared_ptr<Review> &r1, const shared_ptr<Review> &r2)
{
if(r1->price < r2->price)
return true;
else
return false;
}
bool FillReview(Review & rr)
{
cout << "Enter book title(q to quit): ";
getline(cin, rr.title);
if(rr.title == "q")
return false;
cout << "Enter book rating: ";
cin >> rr.rating;
cout << "Enter book price: ";
cin >> rr.price;
if(!cin)
return false;
while (cin.get() != '\n')
continue;
return true;
}
void ShowReview(const shared_ptr<Review> &rr)
{
cout << rr->rating << "\t" << rr->price << "\t" << rr->title << endl;
}
