gistfile1.clj

#!/usr/bin/env clj
(use 'clojure.java.io)
(require ['clojure.contrib.string :as 'string])

(def pairs (first *command-line-args*))

(defn reciprocal-edge? [edges]
  (let [a (nth edges 0)
        b (nth edges 1)]
  (= (take 2 a) (take 2 b))))

(defn transform-weight [weight]
  (Math/round (- (Math/log10 (+ 1e-40 (Float/parseFloat weight))))))

(defn normalise-edge [edges]
  (let [vertices (take 2 (nth edges 1))
        weights  (map #(transform-weight (last %)) edges)]
        (flatten [vertices (apply min weights)])))

(def normalised-edges
  (map normalise-edge
       (filter reciprocal-edge?
               (partition 2 1
                          (map #(string/split #"\s" %)
                  (line-seq (reader pairs)))))))

(doseq [i normalised-edges]
  (println #(apply str (interpose "\t" i))))