第4周项目1-三角形类的构造函数

#include <iostream>

#include <cmath>

using namespace std;

class Triangle

{

public:

Triangle(double x=1,double y=1,double z=1):a(x),b(y),c(z){};

double perimeter();

double area();

void showMessage();

private:

double a,b,c;

};

void Triangle::showMessage()

{

cout<<"三角形的三边长为："<<a<<' '<<b<<' '<<c<<endl;

cout<<"该三角形的周长为"<<perimeter()<<"面积为:"<<area()<<endl<<endl;

}

double Triangle::area()

{

double n,s;

n=(a+b+c)/2;

s=sqrt(n*(n-a)*(n-b)*(n-c));

return s;

}

double Triangle::perimeter()

{

double C;

C=a+b+c;

return C;

}

int main()

{

Triangle Tri(7,8,9);

Tri.showMessage();

return 0;

}