K-sets clojure explorations

kcomb.clj

;; Anything you type in here will be executed
;; immediately with the results shown on the
;; right.

(defn kcomb [k vect]
  (cond 
    (= k 0) '(())
    (empty? vect) '()
    :else (concat (map 
                     #(cons (first vect) %)
                     (kcomb (dec k) (rest vect)))
                  (kcomb k (rest vect)))))




(kcomb 1 [1 2 3])

(defn subsets [n items]
(cond
    (= n 0) '(())
    (empty? items) '()
    :else (concat (map
                    #(cons (first items) %)
                    (subsets (dec n) (rest items)))
                  (subsets n (rest items)))))


(subsets 2 [1 2 3])
(subsets 1 [1 2 3])

(kcomb 3 [1 2 3])
(kcomb 2 [1 2 3])
(kcomb 1 [1 2 3])