Rezolvare problema 1 [Lab. 3]

#lang racket
(define (uncurry->curry f)
  (lambda (x)
    (lambda (y)
      (f x y))))

(define (combine L1 L2 f)
  (foldl (λ (e A) (append A (map ((uncurry->curry f) e) L2))) '() L1))

(define (cartesian L1 L2)
  (combine L1 L2 cons))

(combine '(2 3) '(4 8) +) ; '(6 10 7 11)
(combine '(2) '(1 2 3 4 5) *) ; '(2 4 6 8 10)
(cartesian '(1 2) '(a b c)) ; '((1 a) (1 b) (1 c) (2 a) (2 b) (2 c))
(cartesian '(a) '(X Y)) ; '((a . X) (a . Y))