2-2.cc

一个qt设计的教程

#include <iostream.h>

class car
{
public:
   car();
   void printdata();
   void printweight();
   void printtopspeed();
private:
   int length;
   int width;
   int horsepower;
};

car::car()
{
 cout<<"define the car's length!\n:";
 cin>>this->length;

 cout<<"define the car's width!\n:";
 cin>>this->width;

 cout<<"define the car's horsespeed!\n:";
 cin>>this->horsepower;
}

void car::printdata()
{
 cout<<"\nthis is the car's data:\n";
 cout<<"\nLength:"<<this->length;
 cout<<"\nWidth:"<<this->width;
 cout<<"\nHorse Power:"<<this->horsepower;
 cout<<"\n";
}

void car::printweight()
{
 cout<<"Weight:"<<(this->length*this->width*100);
}

void car::printtopspeed()
{
  if(this->horsepower <= 200)
  {
   cout<<"\nTop Speed:"<<(this->horsepower*1.2)<<"\n"; 
  }
  if(this->horsepower > 200)
  {
   cout<<"\nTop Speed:"<<(this->horsepower*0.8)<<"\n"; 
  }
}

main()
{
  car a_car;
  a_car.printdata();
  a_car.printweight();
  a_car.printtopspeed();
}