Question

我的要求：

定义一个名为里程表的类，用于跟踪汽车的燃油和里程。该类应具有成员变量来跟踪行驶里程和车辆的燃油效率（英里/加仑）。包括一个mutator函数，用于将里程表重置为零英里，一个用于设置燃油效率的mutator函数，一个mutator函数，它接受一个行程驱动的里程并将其添加到里程表的总数，以及一个返回加仑方法，返回加仑数自里程表上次重置以来车辆消耗的汽油。

将您的课程与测试程序一起使用，以创建具有不同燃油效率的多次行程。

  #include <iostream>
 using namespace std;

 class Odometer

  {
 public:

Odometer();

void reset();
void totalfuel();

void input_miles(int getmiles);
void Odometer::set_fuel_efficiency(double fuel_efficiency);

double Odometer::getgallons();
int gallonsUsed;

  private:
int milesDriven;
double fuel_efficiency;
int getmiles;   
};

Odometer::Odometer()
{   
milesDriven = 0;
fuel_efficiency = 0;    
}

void Odometer::reset()
 {
milesDriven = 0;
}

void Odometer::totalfuel()
{
fuel_efficiency = (milesDriven/gallonsUsed);
}

void Odometer::input_miles(int miles_driven)
{
milesDriven = milesDriven + miles_driven;

}

 void Odometer::set_fuel_efficiency(double Fuel_efficiency)
 {
fuel_efficiency = Fuel_efficiency;
 }

 double Odometer::getgallons()
 {
return milesDriven/fuel_efficiency;
 } 


 int main()
 {

  Odometer CarOdometer;
  int number_of_miles_driven;
   double fuel_efficiency;

  cout << "Please enter the amount of miles driven : " << endl;
   cin >> number_of_miles_driven;

CarOdometer.input_miles(number_of_miles_driven);


cout << "Enter Fuel Amount: " << endl;
cin >> fuel_efficiency;

 return 0;
  }

错误：

main.cpp:16:7: error: extra qualification â��Odometer::â�� on member â��set_fuel_efficiencyâ�� [-fpermissive]
  void Odometer::set_fuel_efficiency(double fuel_efficiency);
       ^
main.cpp:18:9: error: extra qualification â��Odometer::â�� on member â��getgallonsâ�� [-fpermissive]
  double Odometer::getgallons();

Answer 1

您的成员函数声明具有封闭类的限定条件。根据C ++标准，这是无效的：

class Odometer {
    void Odometer::member();
};

只需从成员声明中删除多余的资格：

class Odometer {
    void member();
};

Answer 2

只需更改

void Odometer::set_fuel_efficiency(double fuel_efficiency);

double Odometer::getgallons();

到

void set_fuel_efficiency(double fuel_efficiency);

double getgallons();

里程表计划。请提出一些有关此错误的建议

2 个答案: