给定一个集合,我想遍历集合中的所有对。例
(all-pairs seq)
(all-pairs '(a b c d)) => ([a b] [a c] [a d] [b c] [b d] [c d]))
这是我的主意
(defn all-pairs [coll]
(for [ [idx elmt] (indexed coll)
other-elmt (subvec coll (inc idx))]
(vector elmt other-elm)))
但这并不习惯
最佳答案
怎么样:
(use 'clojure.contrib.combinatorics)
(vec (map vec (combinations '(a b c d) 2)))