(2) Design The default constructor, that is, when the parameter is not specified, the default side length is 1. The required test functions are:
int main ()
{
Triangle Tri; //Call the default constructor, when no parameters are specified, the default side length is 1;
Tri.showmessage ();
return 0;
}
#include <iostream> #include <cmath>using namespace Std;class triangle{public: double perimeter (); Double area (); void ShowMessage (); Triangle () { a=1; b=1; c=1; } Private: double a,b,c;}; The three-edged lengths of void Triangle::showmessage () { cout<< "triangles are:" <<a<< "<<b<<" <<c< <endl; cout<< "The circumference of the triangle is" <<perimeter () << ", the area is:" <<area () <<endl<<endl;} Double Triangle::p erimeter () { return a+b+c;} Double Triangle::area () { double p,s; p= (A+B+C)/2; S=sqrt (p* (p-a) * (p-b) * (p-c)); return s;} int main () { Triangle Tri; Tri.showmessage (); return 0;}
Operation Result:
Week four 13 constructors for angular classes-2