6. Modify the FACTOR program in this chapter so that it repeatedly asks for a number and calculates its factorial, until the user enters 0, at which point it terminates.

Chapter 3: 

Loops and Decisions

Programming Exercise

Problem # 6:

Modify the FACTOR program in this chapter so that it repeatedly asks for a number and calculates its factorial, until the user enters 0, at which point it terminates. You can enclose the relevant statements in FACTOR in a while loop or a do loop to achieve this effect.

Solution:

#include <iostream>
using namespace std;
int main()
{
    unsigned int numb;
    unsigned long fact;
    int stop;
  
    cout<<"Enter a number: ";
    cin>>numb;
  
    do
    {
        fact=1;
        for(int j=numb; j>0; j--)
            fact *= j;
          
        cout<<"Factorial is "<<fact<<endl;
        cout<<"Enter a number to continue..."<<endl;
        cout<<"Enter 0 to stop..."<<endl;
        cin>>numb;
    }
    while(numb!=0);

    return 0;
}

Let me know in the comment section if you have any question.

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