sorry "take the first#" actually is meant to be worded as, "in turn, take out 1 of each of the #s, and recurse on what remains" so that you are doing the permutations at each level of the recursion/tree.
On Tue, Aug 14, 2012 at 4:15 PM, Raoul Duke <rao...@gmail.com> wrote: > ¿ > take the first #. > subtract that from the goal. > now ask if the remaining #s can sum to the now-lesser goal. > lather rinse repeat. > don't forget a base case. > watch your cpu heat very quickly up on even slightly longer lists. > ? > > On Tue, Aug 14, 2012 at 4:13 PM, John Holland <jbholl...@gmail.com> wrote: >> I've been doing some programming exercises in Clojure, I've run into one I >> don't know how to approach. If anyone can just give me the strategy to use >> on this that'd be great. Here is the problem statement: >> >> Given an array of ints, is it possible to choose a group of some of the >> ints, such that the group sums to the given target? >> >> >> sample calls would be like: >> >> (groupSum [2, 4, 8] 10) → true >> (groupSum [2, 4, 8] 14) → true >> (groupSum [2, 4, 8] 9) → false >> >> -- >> 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 -- 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
