How to find the largest element in a list of integers recursively?

Question

I\'m trying to write a function which will recursively find the largest element in a list of integers. I know how to do this in Java, but can\'t understand how to do this at Sca

Answer 1

Scala is a functional language whereby one is encourage to think recursively. My solution as below. I recur it base on your given method.

  def max(xs: List[Int]): Int = {
    if(xs.isEmpty == true) 0
    else{
      val maxVal= max(xs.tail)
      if(maxVal >= xs.head) maxVal 
      else                  xs.head     
    }
  }

Updated my solution to tail recursive thanks to suggestions.

  def max(xs: List[Int]): Int = {    
    def _max(xs: List[Int], maxNum: Int): Int = {   
      if (xs.isEmpty) maxNum
      else {
        val max = {
          if (maxNum >= xs.head) maxNum
          else xs.head
        }
        _max(xs.tail, max)
      }
    }
    _max(xs.tail, xs.head)
  }