#lang racket

;; CSE 413 14au
;; Lecture 2 sample code
;; Hal Perkins

(define (twice n) (+ n n))

(define xvii 17)

(define double (lambda (x) (+ x x)))

(define fact (lambda (n) (if (= n 1) 1 (* n (fact (- n 1))))))

(define (weather temp)
  (cond ((> temp 80) 'too-hot)
        ((> temp 60) 'nice)
        ((< temp 40) 'too-cold)
        (else 'seattle)))

(define (len lst)
  (if (null? lst)
      0
      (+ 1 (len (cdr lst)))))