I want to loop this one until the nr-of-bread is 2 how to do it?
(when (and (>= money price-of-bread) (< nr-of-bread 2))
(set! nr-of-bread (+ nr-of-bread 1)) (set! money (- money price-of-bread)))
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Hauleth
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Tolga Yavuz
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1`(quotient money price-of-bread)` – uselpa Nov 07 '15 at 14:30
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3@uselpa rather `(min 2 (quotient money price-of-bread))`. – Hauleth Nov 07 '15 at 14:43
1 Answers
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The best way to achieve that is using tail recursion via named let:
(let loop ((nr-of-bread 0)
(rest money))
(if (and (>= rest price-of-bread) (< nr-of-bread 2))
(loop (add1 nr-of-bread) (- rest price-of-bread))
nr-of-bread))
Hauleth
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Oh… Fixed now. I have been testing it on MIT Scheme on which IIRC Racket is based so I thought that they also have `1+`. But still solves problem. – Hauleth Nov 07 '15 at 14:41
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In Racket you shouldn't use `rest` as a variable name, it clashes with a built-in function. – Óscar López Nov 07 '15 at 17:10