Problem 46

Write a function called countPass that counts the number of elements in an array of elements of type T that pass a test of type T=>Boolean.

Problem 58

A. Most traditional-style recursive functions have similar implementations. Formalize this similarity by implementing a recur combinator that takes two inputs:

def recur(baseVal: Int, combiner: (Int, Int)=>Int): Int=>Int = ???

It returns a traditional-style recursive function f: Int=>Int.

B. Use your recur combinator to implement a factorial function.