; add the first three items
(func first-three (inp)
    (apply + (list (first inp) (first (rest inp)) (first (rest (rest inp))))))

; return 1 if next three greater than first three
(func is-increasing (inp)
    (if (< (first-three inp) (first-three (rest inp)))
        1
        0))

; this works, but i don't like redefining variables
; also this is slow, maybe there needs to be slices
(func iter-list (inp)
    (def acc 0)
    (def prev inp)
    (for-count (- (list-length inp) 3)
        (redef acc (+ acc (is-increasing prev)))
        (redef prev (rest prev)))
    acc)

(def lines 
    (map string->int
        (map strip
            (read-lines "input.txt"))))

(print (->string (iter-list lines)))