Function that multiplies all numbers between "a" and "b" with do loop

Question

I'm making a function that multiplies all numbers between an "a" input and a "b" input with do loop. If you please, check my function and say what's wrong since I don't know loops very well in Scheme.

(define (pi-function x y)
 (let ((result y))
 (do ((limI x (+ x 1)))
 ((= limI y) result)
 (set! result (* result limI)))))

Answer 1

You can use a do loop without using set!.

(define (product-of-range x y)
 (do ((result 1 (* result i))
 (i x (+ i 1)))
 ((> i y) result)))

• gn66: But that doesn't work, when I call (product 1 3) it returns 3, but it should return 6. That function only multiply x for y. What should do, f.e. (product 1 3) (* 1 2) (* 2 3)
• C. K. Young: @gn66: It returns 6 for me. Notice that I updated the function.