scala - Scala中的类型不匹配

Question

我在代码的最后一行有类型不匹配

 def balance(chars: List[Char]): Boolean = {

 def f(chars: List[Char], count: Int) :Boolean= 
  if(chars.isEmpty) {(count==0)}

      else if (chars.head == '(') f(chars.tail,count+1)
      else if(chars.head == ')') f(chars.tail,count-1)
      else f(chars.tail,count) 

 }  //Type mismatch; found: unit required Boolean

Answer 1

balance期望Boolean作为返回值，但您只f在balance. 缺少的可能f(chars, 0)是balance.