(define (range a b)
(if (> a b) '() (cons a (range (add1 a) b))))
(define (sum lst)
(foldl + 0 lst))
(define (sqr a)
(* a a))
(define (problem6 v)
(let ((r (range 1 v)))
(- (sqr (sum r)) (sum (map sqr r)))))
(print (problem6 10))
(print (problem6 100))