return type specification for constructor invalid

[tva274]

For homework, I have to construct a class called "Two_Nums" and there's num1 and num2, in which I will find the sum of their values and average it. I have to use void chg_nums which "mutates" the values of num1 and num2 and void get_nums which "accesses" the values of num1 and num2 using reference variables as arguments.

However, my program is not running. Is there something I messed up on?

#include <iostream>
#include <cmath>

using namespace std;

class Two_Nums
{
      //Declaration of variables as public and private
      private:
              double num1;
              double num2;
      public:
             Two_Nums(double = 10.5, double = 20.5);
             double add();
             double avg();
             
             void chg_nums(double, double);
             void get_nums(double &, double &);
}


Two_Nums::Two_Nums(double n1, double n2)
{
  num1 = n1; 
  num2 = n2; 
}
double Two_Nums::add()
{
       return(num1 + num2);
}
double Two_Nums::avg()
{
       return((num1 + num2)/2);
}

void Two_Nums::get_nums(double &n1, double &n2)
{
     n1 = (this*).num1;
     n2 = (this*).num2;
     
     return; 
}
void Two_Nums::chg_nums(double n1, double n2)
{
     num1 = n1;
     num2 = n2;
     
     return;
}

     
int main()
{
     char ch;
     double n1, n2;
     Two_Nums two1, two2;
     
     two1.get_nums(n1, n2);
     cout<<"By default, num1's value = "<<n1<<endl;
     cout<<"By default, num2's value = "<<n2<<endl;
     cout<<"The sum of num1 & num2 = "<<two1.add()<<endl;
     cout<<"The average of num1 & num2 = "<<two1.avg()<<endl<<endl;
     
     two2.chg_nums(3.5, 9.9); //changed values for num1 and num2
     two2.get_nums(n1, n2);
     cout<<"Changed value for num1 = "<<n1<<endl;
     cout<<"Changed value for num2 = "<<n2<<endl;
     cout<<"The sum of the new values of num1 & num2 = "<<two2.add()<<endl;
     cout<<"The average of the new values of num1 & num2 = "<<two2.avg()<<endl;
     
     cout<<"Press 'e' to exit...";
     cin>>ch;
     
}

I'm getting these errors:

**New types may not be defined in return type & return type specification for constructor invalid
- this goes back to Two_Nums::Two_Nums(double n1, double n2) function

**Expected primary-expression before ')' token
- this goes back to void Two_Nums::get_nums(double &n1, double &n2)
and it refers to the ')' in '(this*)'

[ne555]

You forgot the semicolon at the end of the class declaration

class foo{
   //...
};

it is (*this).num1 or this->num1

[tva274]

@ne555 : Oh wow x.x Thank you so much!