Estrazioni per il secondo torneo di calcetto!

estrazioni.clj

(def players
  [:agostino :alessio :andrea :cesare :domenico :emanuela :fabio
   :francesco :gennaro :jean-pierre :leonardo :luca :nelson :pierpaolo :rosario :sara])

(def old-teams
  (set (map sort [[:agostino :rosario],
   [:alessio :domenico],
   [:emanuela :fabio],
   [:francesco :gennaro],
   [:pierpaolo :cesare],
   [:leonardo :andrea],
   ])))

(defn all-valid-teams?
  "Returns true if all teams are valid (i.e. no old teams)"
  [teams]
  (empty (clojure.set/intersection old-teams teams)))

(loop []
  (let [teams (partition 2 (shuffle players))]
    (if (all-valid-teams? (set (map sort teams))) (println teams) (recur))))