(require 'asdf)

(asdf:load-system "cl-strings")

(require :cl-strings)

(defun diff (data)
  (let* ((lists (reduce (lambda (acc itm) (cons (cons (parse-integer (car itm)) (car acc)) (cons (parse-integer (cadr itm)) (cdr acc))))
                        (mapcar (lambda (line) (cl-strings:split line "   "))
                                (cl-strings:split data "
"))
                        :initial-value (cons (list) (list)))))
    (reduce (lambda (acc itm)
              (+ acc (* (car itm) (cdr itm))))
            (mapcar (lambda (itm) (cons itm (count itm (cdr lists)))) (car lists))
            :initial-value 0)))

(format t "~s~%" (diff "3   4
4   3
2   5
1   3
3   9
3   3"))

(format t "~s~%" (diff (string-right-trim '(#\Space #\Newline) (uiop:read-file-string "input"))))