Question

(55 pts) Write a class Triangle that provides getSides, which returns the lengths of the three sides, and getAngles, which returns the degrees of the three internal angles. Then write a main function that randomly generates an array of triangles and finds the largest triangles first on the basis of area and then on the basis of perimeter

Program in C++ with sample shots.

Thank You.

Answer 1

#include<iostream>

#include<cmath>

#include<cstdlib>

using namespace std;

class Triangle{

   

    // store the length of sides

    double a;

    double b;

    double c;

   

    // store the angle opposite to corresponding sidex

    double A;

    double B;

    double C;

   

    public:

           

        Triangle()

        {

            this->a = 0.0;

            this->b = 0.0;

            this->c = 0.0;

           

            this->A = 0.0;

            this->B = 0.0;

            this->C = 0.0;

        }

       

        // constructor

        Triangle(double a, double b, double c)

        {

            this->a = a;

            this->b = b;

            this->c = c;

           

            // call function to calculate angles

            calculateAngles();

        }

       

        // function to calculate angles using cosine formula

        void calculateAngles()

        {

            //           ( b^2 + c^2 - a^2 )

            // cos(A) = ----------------------

            //                  2a

            this->A = acos( ( pow( this->b , 2 ) + pow( this->c , 2 ) - pow( this->a , 2 ) ) / ( 2.0 * this->a ) ) * 180.0 / 3.14;

            

            //           ( a^2 + c^2 - b^2 )

            // cos(B) = ----------------------

            //                  2b

            this->B = acos( ( pow( this->a , 2 ) + pow( this->c , 2 ) - pow( this->b , 2 ) ) / ( 2.0 * this->b ) ) * 180.0 / 3.14;

           

            //           ( a^2 + b^2 - c^2 )

            // cos(C) = ----------------------

            //                  2c

            this->C = acos( ( pow( this->a , 2 ) + pow( this->b , 2 ) - pow( this->c , 2 ) ) / ( 2.0 * this->c ) ) * 180.0 / 3.14;

        }

   

        // get the sides of triangle

        double* getSides()

        {

            // array to store the sides

            double *sides = new double[3];

           

            sides[0] = this->a;

            sides[1] = this->b;

            sides[2] = this->c;

           

            return sides;

        }

   

        // get the sides of triangle

        double* getAngles()

        {

            // array to store the angles

            double *angles = new double[3];

           

            angles[0] = this->A;

            angles[1] = this->B;

            angles[2] = this->C;

           

            return angles;

        }

       

        double getArea()

        {

            // calculate semi perimeter

            //       a + b + c

            // s = --------------

            //           2

            double s = ( this->a + this->b + this->c ) / 2.0;

           

            // calculate area using heron formula

            double area = sqrt( s * ( s - a ) * ( s - b ) * ( s - c ) );

           

            return area;

        }      

       

        double getPerimeter()

        {

            // perimeter is sum of all sides

            return this->a + this->b + this->c;

        }

       

        void display()

        {

            cout<<"Sides : ("<<this->a<<" , "<<this->b<<" , "<<this->c<<" )\n";

            cout<<"Angles : ("<<this->A<<" , "<<this->B<<" , "<<this->C<<" )\n";

            cout<<"Area : "<<this->getArea()<<endl;

            cout<<"Perimeter : "<<this->getPerimeter()<<endl<<endl;

        }

};

int main()

{

    // genarate sides ranomly in range 1-20

    int a = rand() % 10 + 1;

    int b = rand() % 10 + 1;

    int c = rand() % 10 + 1;

   

    Triangle ob1(a , b , c);

   

    ob1.display();

   

    // genarate sides ranomly in range 1-20

    a = rand() % 10 + 1;

    b = rand() % 10 + 1;

    c = rand() % 10 + 1;

   

    Triangle ob2(a , b , c);

   

    ob2.display();

   

    if( ob1.getArea() > ob2.getArea() )

        cout<<"Area of ob1 is more.\n";

    else

        cout<<"Area of ob2 is more.\n";

       

    if( ob1.getPerimeter() > ob2.getPerimeter() )

        cout<<"Perimeter of ob1 is more.\n";

    else

        cout<<"Perimeter of ob2 is more.\n";

       

    return 0;

}

Sample output

The nan is coming because triangle becomes invalid as the sides are generated randomly.