(define (parzysta n)
  (if (= n 0)
      #t
      (if (< n 0)
          #f
          (parzysta (- n 2)
      ))))

(define (fib n)
  (if (< n 3)
      1
      (+ (fib (- n 2)) (fib (- n 1)))))

(define (ileL n)
  (if (number? n)
      1
      (+ (ileL (car n)) (ileL (cdr n)))))

(define (nalezy? n lst)
  (if (null? lst)
         #f
         (if (equal? (car lst) n)
             #t
             (nalezy? n (cdr lst)))))

(define (polacz lst1 lst2)
  (if (null? lst1)
      lst2
      (cons (car lst1) (polacz (cdr lst1) lst2))))

(define (podziel2 lst)
  (if (null? lst)
      lst
      (cons (/ (car lst) 2) (podziel2 (cdr lst)))))

(define (silniaIT n)
  (silniaITpom n 1))
(define (silniaITpom n accumulator)
  (if (= n 1)
      accumulator
      (silniaITpom (- n 1) (* accumulator n))))

(define (podziel2IT lst)
  (podziel2ITpom lst '()))
(define (podziel2ITpom lst accumulator)
  (if (null? lst)
      accumulator
      (podziel2ITpom (cdr lst) (append accumulator (list (/ (car lst) 2))))))