Question

**指南：**为户主，年收入和家庭成员获得3个单独的数据（数组）列表，然后获得所有年收入并将它们平均在一起。在整洁的表格中显示。

这是来自一个学校项目我不允许使用任何非常先进的东西，但我现在想回去改进它。我想让它变得更干净，特别想找到更多可以带走它的东西，而不是添加它。

// <Program Name> Programming Project #3 Average Income (Using Functions and Arrays)
// <Author> Brendan Jackson
// <Date of Programs Release> 08/05/15
// <Program Description> takes 3 arrays and displays them with average income
#include <iostream> // allows cin and cout statements
#include <iomanip> //allows setprecision
#include <string> //allows strings
using namespace std; // Namespace std allows program to use entities from <iostream>

int input(string[], int[], double[]); //function 1
double calculate_average_income(double[], int);  //function 2
void display_survey_data(string[], int[], double[],int , double);  //function 3


int main() // main function
{

    //variables for functions
    string name[10];

    int members[10];

    double income[10];

    int count_of_households;

    double average;

    //get input
    count_of_households = input(name, members, income);

    //calculate average
    average = calculate_average_income(income, count_of_households);


    //output all data in table
    display_survey_data(name, members, income, count_of_households, average);


    return 0;

}


int input(string name[], int members[], double income[]) //function 1
{

    // get household info
    int count_of_households = 0;

    cout << "How many house holds were there? ";
    cin >> count_of_households;
    //TODO: handle bad input (characters and decimals)
    if (count_of_households >= 11 || count_of_households < 0) 
    {
        cout << "must enter valid # " ; //TODO: more description
        count_of_households = 0; //set back to safe value
    }
    else 
    {

           //cycle through arrays                  
        for (int count = 0; count < count_of_households; count++) //TODO:  take out (count + 1) start from 1 alternatively
        {

            // get survey info for names
            cout << "Enter household #" << (count + 1) << "'s head of household name\t"  ;
            cin.ignore() ; // ignores keyboard buffer characters
            getline (cin, name[count]) ; 


            // get survey info for income
            cout << "Enter household #" << (count + 1) << "'s annual income\t"  ;
            cin >>  income[count];


            // get survey info for members
            cout << "Enter household #" << (count + 1) << "'s household members\t"  ;   
            cin >>  members[count]; 
        }   
    }
    return count_of_households;
}

double calculate_average_income(double income[], int count_of_households) //function 2
{


    //add incomes together
    double total = 0.0;
    double average = 0.0;

    //loop over income
    for (int count = 0 ; count < count_of_households; count++)
    {
        //add income to runnning total
        total += income[count];  
    }

    // save calculations
    average = total / count_of_households; 
    return average;
}




void display_survey_data(string name[], int members[], double income[],int count_of_households, double average) //funtion 3
{
    //print out header
    cout << setw(30) << ""
         << setw(30) << ""
         << setw(30) << "NUMBER OF\n" ;
    cout << setw(30) << "HOUSEHOLD NAME"
         << setw(30) << "ANNUAL INCOME"
         << setw(30) << "HOUSEHOLD MEMBERS\n" ;
    cout << setw(30) << "--------------------" 
         << setw(30) << "---------------" 
         << setw(30) << "------------------------\n" ;      
    ///loop over values
    for (int count = 0 ; count < count_of_households; count++)
    {
        cout << setw(30) << name[count]
             << setw(30) << setprecision(2) << fixed << showpoint << income[count]
             << setw(30) << members[count] 
             << endl;   
    }   
    // display average
    cout << endl
         << setw(30) << "AVERAGE INCOME"
         << setw(30) << average
         << endl;
}

Answer 1

您可以使用std::array

这只是堆栈上的一个数组，就像你使用的那样，但它有迭代器，类型安全，绑定安全，使用值语义并且可以使用大多数stl算法。

声明如下：

array<string, 3> myArray;

它必须通过引用传递，因为按值传递将复制它的内容：

void doSomething(array<int, 6>& aArray) {
    // do something
}

请注意，您必须指定数组的长度，因为它是模板参数。如果您想拥有任何大小的数组，请使用tempaltes：

template<size_t length>
void foobar(array<double, length> theArray) {
    // do something else
}

如果没有载体，我怎么能改进这个c ++程序？

1 个答案: