三角类

include<iostream>#include<Cmath>using namespace std;class Triangle{public:   inlinevoid setA(double x)//置三边的值，注意要能成三角形{a=x;}inlinevoid setB( double x){b=x;}inlinevoid setC( double x){c=x;}inlineint getA()//取三边的值{return a;}inlineint getB(){return b;}inlineint getC(){return c;}    void setABC(double x, double y, double z);//置三边的值，注意要能成三角形void getABC(double *x, double *y, double *z);//取三边的值bool isTriangle();double perimeter(void);//计算三角形的周长double Area(void);//计算并返回三角形的面积private:double a,b,c; //三边为私有成员数据};int main(){Triangle tri1;//定义三角形类的一个实例（对象）double x,y,z;cout<<"请输入三角形的三边：";cin>>x>>y>>z;tri1.setA(x);tri1.setB(y);tri1.setC(z);//为三边置初值if(tri1.isTriangle()){ cout<<"三条边为："<<tri1.getA()<<','<<tri1.getB()<<','<<tri1.getC()<<endl;cout<<"三角形的周长为："<< tri1.perimeter()<<'\t'<<"面积为："<< tri1.Area()<<endl;}elsecout<<"不能构成三角形"<<endl;system("pause");return 0;}bool  Triangle::isTriangle()  {      if((a+b)>c&&(a-b)<c)          return true;      else           return false;  }  void Triangle::setABC(double x ,double y, double z){if(x+z>y&&y+x>z&&z+y>x){    a=x;     b=y;     c=z;}else{a=0;b=0;c=0;}}void Triangle::getABC(double *x,double*y,double*z){ *x=a; *y=b; *z=c;}double Triangle::perimeter(void){ return a+b+c;}double Triangle::Area(void){double p=(a+b+c)/2;return sqrt(p*(p-a)*(p-b)*(p-c));}

运行结果：