program callit
      integer n, i, k1, k2, k3
      real c 
      print*, 'Enter N & I (N bigger than I)'
      read*, n,i 
      k1=ifact(n)
      k2=ifact(i)
      k3=ifact(n-i)
      c=k1/k2/k3
      print*,'C = ',c 
      end