racket-random/pascal-line.rkt
joachimschmidt557 7bbf3a5070 wip
2020-01-29 16:30:13 +01:00

10 lines
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626 B
Racket

;; The first three lines of this file were inserted by DrRacket. They record metadata
;; about the language level of this file in a form that our tools can easily process.
#reader(lib "htdp-advanced-reader.ss" "lang")((modname pascal-line) (read-case-sensitive #t) (teachpacks ()) (htdp-settings #(#t constructor repeating-decimal #t #t none #f () #f)))
(define (pascal-line n)
(cond [(= n 0) (list 1)]
[else (new-pascal-line (append (list 0) (pascal-line (- n 1)) (list 0)))]))
(define (new-pascal-line l)
(cond [(< (length l) 2) empty]
[else (cons (+ (first l) (second l)) (new-pascal-line (rest l)))]))