why it does not give proper result when member function is called without values

Question

why my code does not work when i call the gett function and try to print the output(second code) where as it gives proper output when i pass the argument from main(first code). I called my function using rs.power(arguments) in first and in second using get function i am getting - output in the second code

code-1

#include<iostream>
#include<cmath>
using namespace std;
class powm
{
public:
double result;

public:
inline power(double m,double n)
{
    result=pow(m,n);     
}
void display()
{
    cout<<result;
}
}rs;
int main()
{
    double a,b;
    cout<<"We are calculating the power of the number "<<endl;
    cout<<"Enter the number :"<<endl;
    cin>>a;
    cout<<"enter the power :"<<endl;
    cin>>b;
    rs.power(a,b);
    rs.display();
    return 0;
}

Code-2

#include<iostream>
#include<cmath>
using namespace std;
class powm
{
public:
double result,a,b;

public:
void gett()
{   
    cout<<"We are calculating the power of the number "<<endl;
    cout<<"Enter the number :"<<endl;
    cin>>a;
    cout<<"enter the power :"<<endl;
    cin>>b;
}
inline power()
{
    result=pow(a,b);     
}
void display()
{
    cout<<result;
}
}rs;
int main()
{
    
    rs.gett();
    rs.display();
    return 0;
}

Answer 1

In the second code block, you haven't done anything to compute result.

Try

rs.gett();
rs.power();
rs.display();

---

I would recommend using:

#include <iostream>
#include <cmath>

using namespace std;

class powm
{
   public:
      double result;

   public:
      // Make sure constructor initializes the member variables appropriately.
      powm(double m,double n) : result(pow(m,n)) {}
};

// Separate display to a non-member function.
// Make it general and not hard coded to output to cout.
std::ostream& operator<<(std::ostream& out, powm const& p)
{
   return out << p.result;
}

int main()
{
   double a,b;
   cout<<"We are calculating the power of the number "<<endl;
   cout<<"Enter the number :"<<endl;
   cin>>a;
   cout<<"enter the power :"<<endl;
   cin>>b;

   // Construct object.
   powm rs(a,b);

   // Display to cout.
   cout << rs << ened;

   return 0;
}