Thank you to anyone who has already donated - your generous donations helped make three months of treatment possible.

My brother Nate continues to fight stage IV Hodgkin's lymphoma. He's just 31, with a wife and baby girl. They have no active income (since he's been unable to return to work), no insurance, and cannot afford the treatment he needs. Nate and his family need your help. Please consider a donation, every dollar helps. Thanks.

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#lang racket

(require racket/future)

(define (sum values)
  (foldr + 0 values))

(define (best vals-1 vals-2 target)
  (if (< (abs (- target (sum vals-1)))
         (abs (- target (sum vals-2))))
      vals-1
      vals-2))

(define (closest values target)
  (cond [(= 1 (length values))
         values]
        [(= 0 target)
         '()]
        [else
         (let ([wout-first
                (future (λ () (closest (rest values) target)))]
               [with-first 
                (future (λ () (closest (rest values) (- target (first values)))))])
           (best (touch wout-first) (cons (first values) (touch with-first)) target))]))