[خزان الأحزان]

للفائدة

إن كانت النتائج صحيحة حمل الكود وإن لم تكن عدله بما يناسبك

#include<iostream>

using namespace std;

int Factorial(int N)     // Function of (Number)!
{                   
      int F;
      F = 1;
      for( ; N > 0 ; )
      {
           F = F * N ; 
           N = N - 1 ;
            }
      return F;       }
      
float Formula(int n , int r,int NR)  // Function of Formula
{
      float Solve = 0;
      Solve = Factorial(n) / ( Factorial(r) * Factorial(NR));
      
      return Solve;
      }
int main(){
    //----------------------Define Variables
    int n;
    int r;
    int n_r;
    
    //----------------------real code    
    cout << "\n\n\t ==========================\n\t  Define Variables \
    \n\t -------------------------- \n\t Insert n : ";
    cin >> n;
    cout << "\t Insert r : ";
    cin >> r;
    n_r = n - r;
    cout << "\n\n\t ==========================\n\t  Variables Factory \
    \n\t -------------------------- \n\t n! = " << Factorial(n)<< endl; // N!
    cout << "\t r! = " << Factorial(r)<< endl;
    cout << "\n\n\t ==========================\n\t  Solve of Formula \
    \n\t -------------------------- \n\t n!/(r! * (n-r)!) = " << Formula(n,r,n_r)<<endl<<endl<<endl;
    
    system("pause");
    return 0;
}