nth is called in doing the destructuring for the argument lists in your fns defined in try-find-sequence.
On Tue, Dec 11, 2012 at 1:20 PM, Dennis Haupt <d.haup...@gmail.com> wrote: > i am trying to solve euler problem 125. when i tested this code: > > (ns euler.Problem125) > > (defn is-palindrome [n] > (let [s (str n)] > (= (seq s) (reverse s)))) > > (defn to-check [] > (filter is-palindrome (range 1 1000))) > > (defn square-root [n] > (Math/sqrt n)) > > (defn squared [n] > (* n n)) > > (defn try-find-sequence [n] > (loop [start-at (int (square-root n))] > (let [combinator (fn [[sum smallest] element] [(+ sum element) (dec > element)]) > reduced (reduce combinator [0 start-at] (range start-at 0 -1)) > pred (fn [[sum smallest]] (> sum n)) > until-match-or-overflow (take-while pred reduced) > solution-or-not (last until-match-or-overflow)] > (cond > (= (first solution-or-not) n) nil > (= (first solution-or-not) n) (second solution-or-not) > :else (recur (dec start-at)))))) > (println (try-find-sequence 595)) > > i get: > Exception in thread "main" java.lang.UnsupportedOperationException: nth > not supported on this type: Long > at clojure.lang.RT.nthFrom(RT.java:846) > at clojure.lang.RT.nth(RT.java:796) > at > euler.Problem125$try_find_sequence$pred__16.invoke(Problem125.clj:20) > at clojure.core$take_while$fn__4116.invoke(core.clj:2512) > > but why? i don't call nth on anything! > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with your > first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en -- Ben Wolfson "Human kind has used its intelligence to vary the flavour of drinks, which may be sweet, aromatic, fermented or spirit-based. ... Family and social life also offer numerous other occasions to consume drinks for pleasure." [Larousse, "Drink" entry] -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
