Scala 递归函数

递归函数

递归在纯函数式编程中起着重要作用，而Scala很好地支持递归函数。递归意味着函数可以重复调用自身。尝试以下程序，这是递归的一个很好的示例，其中计算了传递的数字的阶乘。

object Demo {
   def main(args: Array[String]) = {
      for (i <- 1 to 10)
         println( "Factorial of " + i + ": = " + factorial(i) )
   }

   def factorial(n: BigInt): BigInt = {  
      if (n <= 1)
         1  
      else    
      n * factorial(n - 1)
   }
}

输出：

Factorial of 1: = 1
Factorial of 2: = 2
Factorial of 3: = 6
Factorial of 4: = 24
Factorial of 5: = 120
Factorial of 6: = 720
Factorial of 7: = 5040
Factorial of 8: = 40320
Factorial of 9: = 362880
Factorial of 10: = 3628800