C++ primer 第五章 编程练习题

题目1

题目2

题目3

第一题

#include<iostream>
#include<string>
#include<array>
using namespace std;



int main()
{
    int a, b;
    cout << "请输入较小的整数：";
    cin >> a ;
    cout << "请输入较大的整数：";
    cin >> b ;
    int sum = 0;
    while (a <= b)
    {
        sum = sum + a;
        a++;
    }
    cout <<"所有整数和为：" << sum<<endl;
    system("pause");
    return 0;
}

程序5.4

#include<iostream>
#include<array>
using namespace std;
const int ArSize = 16;
int main()
{
    array<long double, ArSize> factorials;
    factorials[1] = factorials[0] = 1;
    for (int i = 2; i < ArSize; i++) {
        factorials[i] = i * factorials[i - 1];

    }
    for (int i = 0; i < ArSize; i++)
    {
        cout << i << " != " << factorials[i] << endl;
    }
    system("pause");
    return 0;
}

#include<iostream>
using namespace std;
int main()
{
    int number,sum = 0;
    cout << "请输入数字：" ;
    cin >> number;
    while (number != 0)
    {
        sum = sum+number;
        cout << "累计和为：" << sum<<endl;
        cout << "请输入数字：" ;
        cin >> number;
    }
    system("pause");
    return 0;
}

#include<iostream>
using namespace std;
int main()
{
    double Daphne, Cleo;
    Daphne = Cleo = 100.0;
    int year=1;
    while (Cleo <= Daphne) {
        Cleo += (Cleo) * 0.05;
        Daphne += 10;
        year++;
    }
    cout << "it will take " << year-1 << " years that Cleo's investment value exceeds Daphne's investment value.\n";
    cout << "Now the Cleo's investment is " << Cleo << endl;
    cout << "And the Daphne's investment is " << Daphne << endl;

    return 0;
}

#include<iostream>
using namespace std;
int main()
{
    string arr[] = { "一月份","二月份" ,"三月份" ,"四月份" ,"五月份" ,"六月份" ,"七月份" ,"八月份" ,"九月份" ,"十月份" ,"十一月份" ,"十二月份" };
    int amount[12];
    int sum = 0;
    for (int i = 1;i <= 12;i++) {
        cout << "请输入" << arr[i - 1] << "的图书数量：";
        cin >> amount[i - 1];
        sum += amount[i - 1];
    }
    cout << "图书总数为：" << sum << endl;

    system("pause");
    return 0;
}

输出结果为：

结果.png

#include<iostream>
using namespace std;
int main()
{
    string arr[] = { "一月份","二月份" ,"三月份" ,"四月份" ,"五月份" ,"六月份" ,"七月份" ,"八月份" ,"九月份" ,"十月份" ,"十一月份" ,"十二月份" };
    int amount[3][12];
    int sum_year = 0;
    int sum = 0;
    for (int year = 1;year <= 3;year++) {
        string arr_year[] = { "第一年","第二年","第三年" };
        cout << "请输入" << arr_year[year-1] << "的数量" << endl;
        for (int i = 1;i <= 12;i++) {
            cout << "请输入" << arr[i - 1] << "的图书数量：";
            cin >> amount[year-1][i-1];
            sum_year += amount[year - 1][i - 1];
        }
        cout << "本年的图书总数为："<<sum_year<<endl;
        sum += sum_year;
        sum_year = 0;
    }
    cout << "图书总数为：" << sum << endl;

    system("pause");
    return 0;
}

运行结果

#include<cstring>
using namespace std;
struct collection {
    char name[100];
    int year;
};

int main()
{
    int amount;
    cout << "How many cars do you wish to catalog?";
    cin >> amount;
    cin.get();
    collection car[100];
    for (int i = 1;i <= amount;i++)
    {
        cout << "Car #" << i << endl;
        cout << "Please enter the make:";
        cin.get(car[i].name, 100).get();
        cout << "Please enter the year made:" << endl;
        cin >> car[i].year;
        cin.get();
    }

    cout << "Here is your collection:" << endl;
    for (int i = 1;i <= amount;i++) {
        cout << car[i].year << " " << car[i].name << endl;
    }
    system("pause");
    return 0;
}

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

int main()
{
    char  word[100];
    int i = 0;
    cout << "Enter words(to stop,type the word done):" << endl;
    while (cin >> word && strcmp(word, "done"))
        i++;
    cout << "you entered a total of" << i << "words." << endl;
    system("pause");
    return 0;
}

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

int main()
{
    string word;
    int i = 0;
    cout << "Enter words(to stop,type the word done):" << endl;
    while (cin>>word && word != "done")
        i++;
    cout << "you entered a total of " << i << " words." << endl;
    system("pause");
    return 0;
}

比如：
while（！（cin>>golf[i]））{
...，
}
如果用户输入88，cin将为true，!(cin>>golf[i]）将为false

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

int main()
{
    int column;
    cout << "请输入行数：";
    cin >> column;
    for (int i = 0;i <column;i++) {
        cin.get();
        for (int j = (column - i);j != 1;j--) {
            cout << ". ";
        }
        for (int k = (i+1);k!=0;k--) {
            cout << "* ";
        }
    }
    cin.get();
    system("pause");
    return 0;
}

运行结果