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Problem Set 2 Comments

The PS2 Comments are posted on the course website.
(define (find-best f p)
  (if (null? (cdr p))
      (car p)
      (pick-best f (car p)
                   (find-best f (cdr p)))))

(define (pick-best f a b)
   (if (f a b) a b))
How can we define find-best-hand using find-bestiest?

Mapping Lists

Define a procedure list-map that takes two inputs, a procedure and a list and produces as output a list whose elements are the results of applying the input procedure to each element in the input list.

What do each of these expressions mean:
(define (mystery-one p)
   (list-map (lambda (x) (if (< x 0) (- x) x))) p))

(define (mystery-two p)
   (list-map list-sum p))

(define (mystery-three p)
     (lambda (q)
       (list-map (lambda (n) (odd? n)) q))

Could you use list-map to count the number of odd numbers in a list?

Could you use list-map to produce a list that is the input list with all the odd numbers removed? (e.g., input: (1 2 3 4), output: (2 4)).