factor2.cpp

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//factor2.cpp
//calculates factorials using recursion
#include <iostream>
using namespace std;

unsigned long factfunc(unsigned long);  //declaration

int main()
   {
   int n;                //number entered by user
   unsigned long fact;   //factorial
   
   cout << "Enter an integer: ";
   cin >> n;
   fact = factfunc(n);
   cout << "Factorial of " << n << " is " << fact << endl;    
   return 0;
   }   
//-------------------------------------------------------------
// factfunc()
// calls itself to calculate factorials
unsigned long factfunc(unsigned long n)
   {
   if(n > 1)
      return n * factfunc(n-1);  //self call
   else
      return 1;
   }