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#lang racket
;; import miller raban prime test
(load "coding-exercises/1/28.rkt")
;; sum of squares of the prime numbers in the interval a to b
(define (prime? x)
(all-mr x))
(define (filtered-accumulate pred combiner null-value term a next b)
(define (iter a result)
(cond
((> a b) result)
((pred a) (iter
(next a)
(combiner
(term a)
result)))
(else (iter (next a) result))))
(iter a null-value))
(define (square-prime-sum a b)
(filtered-accumulate
prime?
(lambda (x y) (+ x y))
0
(lambda (x) (* x x))
a inc b))
(square-prime-sum 2 5)
(define (coprime-product n)
(define (coprime? a)
(if (= 1 (gcd a n))
((lambda ()
(println a)
true))
false))
(filtered-accumulate
coprime?
(lambda (x y) (* x y))
1
(lambda (x) x)
1 inc (- n 1)))
(coprime-product 10)
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