Answer to Question #194383 in C++ for Taj Pathan

Question

Write a C++ program which perform the following:

1. Create a Class factorial

2. Create Private Member Variable and initialize it with Member 

initialization list and with value zero

3. Now, take inputs from user

4. Create a Public Member Function Calculate( ) outside the class, 

to calculate the factorial of a given input

5. Create another Public Member Function Result( ) outside the 

class, to print the results on screen

6. Now, create a constant object of the class which perform following: 

a. Passes the values to the Calculate( ) function 

b. Call the Result( ) function to show result

Answer 1

#include<iostream>
using namespace std;
class Factorial
{
    int n;
public:
    Factorial(int i=0):n(i){}
    int access()const
    {
        return n;
    }
    unsigned long int Calculate()const;
    void display()const;
};
unsigned long int Factorial::Calculate()const
{
    unsigned long f=1;
    int i=0,j;
    j=access();
    for(i=1;i<=j;i++)
    {
        f=f*i;
    }
    return f;
}
void Factorial::display()const
{
    cout<<"\nFactorial of "<<access()<<" is equal to "<<Calculate();
}
int main()
{
    const Factorial f1;
    int* ptr=(int*)&f1;
    int n1;
    cout<<"Enter the number whose factorial is to be calculated ";
    cin>>n1;
    *ptr=n1;
    f1.display();
}