graph_find.clj

(require 'clojure.set)

(def connections
  ["3-4"
   "4-9"
   "8-0"
   "2-3"
   "5-6"
   "2-9"
   "5-9"
   "7-3"
   "4-8"
   "5-6"
   "0-2"
   "6-1"
   "11-12"
   "11-16"])

(defn path->pair
  [path]
  (map #(Integer/parseInt %) (.split path "-")))

(defn graph-find
  [connections x]
  (some (partial clojure.set/subset? x)
        (reduce (fn [acc path]
                  (let [pair (path->pair path)
                        pred (partial some (set pair))
                        [connected disconnected] ((juxt filter remove) pred acc)]
                    (set (cons (set (apply concat pair connected)) disconnected))))
                #{}
                connections)))