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(define (cons x y)
(define (dispatch m)
(cond ((= m 0) x)
((= m 1) y)
(else
(error "Argument not 0 or 1:
CONS" m))))
dispatch)
(define (car z) (z 0))
(define (cdr z) (z 1))
(define pair (cons 111 2))
(car pair)
;Exercise 2.4
(define (cons x y)
(lambda (m) (m x y)))
(define (car z)
(z (lambda (p q) p)))
(define (cdr z)
(z (lambda (p q) q)))
(cdr (cons 1 2))
;Exercise 2.5
(define (cons x y) (* (pow 2 x) (pow 3 y)))
(define (pow x y)
(if (= y 0)
1
(* x (pow x (- y 1)))))
(define (car z)
(if (not (= (modulo z 2) 0))
0
(+ (car (/ z 2)) 1)))
(define (cdr z)
(if (not (= (modulo z 3) 0))
0
(+ (cdr (/ z 3)) 1)))
(car (cons 10 2))
(cdr (cons 1 119))
;Exercise 2.6
(define zero (lambda (f) (lambda (x) x)))
(define (add-1 n)
(lambda (f) (lambda (x) (f ((n f) x)))))
(define one (lambda(f) (lambda (x) (f x))))
(= one (add-1 zero))
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