module Math
   export comb

      { ok, factorial is used by an exported routine }
   routine factorial( int n ) -> int 
      is 
         if n > 1
            return n*factorial(n-1)
         else
            return 1
      end factorial

     { ok, this routine is exported }
   routine comb(int m, int n) -> int
      is
         return factorial(m)/(factorial(n)*factorial(m-n))
      end comb

      { this routine will never be called }
   routine sumTill(int n) -> int
      local int sum
      is
         i = 1
         sum = 0
         loop
            exiton i >= n
            sum = sum + factorial(i)
            i = i + 1
         endloop
         return sum
      end sumTill

end Math