Scala 递归函数

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  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)
     }
  }
  

  尝试一下

  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