09.cpp

#include <iostream>
using namespace std;

int main(){
  int n,count,product,sum,fac;
  char answ;
  cout<<"This program calculate the factorial of a number."<<endl;
  do {
    cout <<"Please type an positive number: ";
    cin >> n;
    count=1;
    product=1;
    sum=1;
    if (n>1) {
      do{
        count++;
        product=product*(sum+1);
        sum++;
        fac=product;
      }while (count!=n);
      cout <<"The factorial of "<<n<<" is: "<<fac<<endl;
      cout <<"Would you like to type another number (y/n)?";
      cin >> answ;
    } else {
      if (n==1) {
        cout <<"The factorial of 1 is: 1"<<endl;
        cout <<"Would you like to type another number (y/n)?"<<endl;
        cin>>answ;
      } else {
        cout<<"The number that you enter was negative, please try again."<<endl;
        answ='y';
      }
    }
  } while(answ=='y');
}