C清华大学出版社第4版课件第4章.pptVIP

第四章 类与对象;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;*;void Clock::setTime(int newH, int newM, int newS) { hour = newH; minute = newM; second = newS; } void Clock::showTime() { cout hour : minute : second; };*;*;*;*;*;inline void Point:: init(int initX,int initY) { x = initX; y = initY; } inline int Point::getX() { return x; } inline int Point::GetY() { return y; };*;*;*;*;*;构造函数的实现： Clock::Clock(int newH, int newM, int newS) { hour = newH; minute = newM; second = newS; } 建立对象时构造函数的作用： int main() { Clock c(0,0,0); //隐含调用构造函数，将初始值作为实参。 c.showTime(); return 0; };*;*;Point::Point (Point p) { x = p.x; y = p.y; cout Calling the copy constructor endl; };*;*;*;*;*;*;Point::Point(int xx,int yy) { x = xx; y = yy; } Point::~Point() { } //...其他函数的实现略;*;#include iostream using namespace std; const float PI = 3.141593; //给出p的值 const float FENCE_PRICE = 35; //栅栏的单价 const float CONCRETE_PRICE = 20;//过道水泥单价 class Circle { //声明定义类Circle 及其数据和方法 public: //外部接口 Circle(float r); //构造函数 float circumference(); //计算圆的周长 float area(); //计算圆的面积 private: //私有数据成员 float radius; //圆半径 };;//类的实现 //构造函数初始化数据成员radius Circle::Circle(float r) { radius = r; } //计算圆的周长 float Circle::circumference() { return 2 * PI * radius; } //计算圆的面积 float Circle::area() { return PI * radius * radius; };int main () { float radius; cout Enter the radius of the pool: ; // 提示用户输入半径 cin radius; Circle pool(radius); //游泳池边界 Circle poolRim(radius + 3); //栅栏 //计算栅栏造价并输出 float fenceCost = poolRim.circumference() * FENCE_PRICE; cout Fencing Cost is $ fenceCost endl;; //计算过道造价并输出 float concreteCost = (poolRim.area() - pool.area()) * CONCRETE_PRICE; cout Concrete Cost is $ concreteCost endl; return 0; } 运行结果 Enter the radius of the pool: 10 Fencing Cost is $2858.85 Concrete Cost is $4335.4;*;*;class Line { private: Point p1, p2; //线段的两个端点 public: Line(Point a, Point b); //构造函数 void draw(void); //画出线段 }; //...函数