【C++】学习笔记十四——C++ primer plus第六版第4章编程练习

1.

//4.13编程练习 1#include<iostream>#include<string>int main(){    using namespace std;    enum grade {A, B, C, D};    cout << "What is your first name? ";    string first_name;    getline(cin, first_name);    cout << "What is your last name? ";    string last_name;    cin >> last_name;    cout << "What letter grade do you deserve? ";    char grade;    cin >> grade;    cout << "What is your age? ";    int age;    cin >> age;    cout << "Name: " << last_name << ", " << first_name << endl;    cout << "Grade: " << char(grade + 1) << endl;    cout << "Age: " << age;    cin.get();    cin.get();    return 0;}

2.

#include<iostream>#include<string>int main(){    using namespace std;    string name;    string dessert;    cout << "Enter your name:\n";    getline(cin,name);       //读取一行    cout << "Enter your favorite dessert:\n";    getline(cin,dessert);    cout << "I have some delicious " << dessert;    cout << " for you, " << name << ".\n";    cin.get();    cin.get();    return 0;}

3.

#include<iostream>#include<cstring>int main(){    using namespace std;    cout << "Enter your first name: ";    char firstname[20];    cin >> firstname;    cout << "Enter your last name: ";    char lastname[20];    cin >> lastname;    char name[40];    strcpy(name, lastname);    strcat(name, ", ");    strcat(name, firstname);    cout << "Here's the information in a single string: " << name;    cin.get();    cin.get();    return 0;}

4.

#include<iostream>#include<string>int main(){    using namespace std;    cout << "Enter your first name: ";    string firstname;    cin >> firstname;    cout << "Enter your last name: ";    string lastname;    cin >> lastname;    string name = lastname + ", " + firstname;    cout << "Here's the information in a single string: " << name;    cin.get();    cin.get();    return 0;}

5.

#include<iostream>#include<string>using namespace std;struct CandyBar{    string brand;    double weight;    int calorie;};int main(){    CandyBar snack    {        "Mocha Munch",        2.3,        350    };    cout << "snack: " << endl;    cout << "brand: " << snack.brand << endl;    cout << "weight: " << snack.weight << endl;    cout << "calorie: " << snack.calorie << endl;    cin.get();    return 0;}

6.

#include<iostream>#include<string>using namespace std;struct CandyBar{    string brand;    double weight;    int calorie;};int main(){    CandyBar snack[3]    {        {"Mocha Munch", 2.3, 350}, {"Dabaitu", 5.6, 520}, {"Wowo", 3.6, 450}    };    int i;    for (i = 0; i < 3; i++)    {        cout << "Candy " << i << endl;        cout << "\tbrand: " << snack[i].brand << endl;        cout << "\tweight: " << snack[i].weight << endl;        cout << "\tcalorie: " << snack[i].calorie << endl;    }    cin.get();    return 0;}

7.

#include<iostream>#include<string>using namespace std;struct William{    string company_name;    double pizza_diameter;    double pizza_weight;};int main(){    William pizza;    cout << "Enter the name of the company: ";    getline(cin, pizza.company_name);    cout << "Enter the diameter of the pizza: ";    cin >> pizza.pizza_diameter;    cout << "Enter the weight of the pizza:";    cin >> pizza.pizza_weight;    cout << "pizza: ";    cout << "\tCompany: " << pizza.company_name << endl        << "\tdiameter: " << pizza.pizza_diameter << endl        << "\tweight: " << pizza.pizza_weight << endl;    cin.get();    cin.get();    return 0;}

8.

#include<iostream>#include<string>using namespace std;struct William{    string company_name;    double pizza_diameter;    double pizza_weight;};int main(){    William * pizza = new William;    cout << "Enter the diameter of the pizza: ";    cin >> pizza->pizza_diameter;    cout << "Enter the name of the company: ";    cin.get();                                  //输入直径后，输入队列中还有换行符    getline(cin, pizza->company_name);    cout << "Enter the weight of the pizza:";    cin >> pizza->pizza_weight;    cout << "pizza: ";                                                 cout << "\tCompany: " << pizza->company_name << endl        << "\tdiameter: " << pizza->pizza_diameter << endl        << "\tweight: " << pizza->pizza_weight << endl;    delete pizza;    cin.get();    cin.get();    return 0;}

9.

#include<iostream>#include<string>using namespace std;struct CandyBar{    string brand;    double weight;    int calorie;};int main(){    CandyBar * snack = new CandyBar[3];    snack[0] = { "Mocha Munch", 2.3, 350 };    snack[1] = { "Dabaitu", 5.6, 520 };    snack[2] = { "Wowo", 3.6, 450 };    int i;    for (i = 0; i < 3; i++)    {        cout << "Candy " << i << endl;        cout << "\tbrand: " << snack[i].brand << endl;        cout << "\tweight: " << snack[i].weight << endl;        cout << "\tcalorie: " << snack[i].calorie << endl;    }    delete [] snack;        //不要忘记delete，不要忘记[]    cin.get();    return 0;}

10.

#include<iostream>#include<array>int main(){    using namespace std;    array<double, 3> grade;    cout << "Enter your first grade: ";    cin >> grade[0];    cout << "Enter your second grade: ";    cin >> grade[1];    cout << "Enter your third grade: ";    cin >> grade[2];    double grade_avr = (grade[0] + grade[1] + grade[2]) / 3;    cout << "The average grade of your 3 times grades is " << grade_avr;    cin.get();    cin.get();    return 0;}