(define runaway-strategy
  (lambda (gh g)
    (letrec ((p (game-pacman g))
             (c (ghost-col gh))
             (r (ghost-row gh))
             (dir (ghost-dir gh))
             (d-up (distance p c (- r 1)))
             (d-down (distance p c (+ r 1)))
             (d-left (distance p r (- c 1)))
             (d-right (distance p r (+ c 1)))
             (crossing-code (direction-map/coordinate
                              (maze-direction-map
                               (field-maze
                                (game-field g)))
                              c r))
             (poss-dirs (code->direction crossing-code))
             (distances (map (lambda (x)
                               (cond ((string=? "up" x) d-up)
                                     ((string=? "down" x) d-down)
                                     ((string=? "left" x) d-left)
                                     ((string=? "right" x) d-right))) poss-dirs))
             (maxdist (fold 0 max distances)))
      (cond
        ((= maxdist 0) dir)
        ((and (any? (lambda (x) (direction=? "down" x)) poss-dirs) (= d-down maxdist))  "down")
        ((and (any? (lambda (x) (direction=? "up" x)) poss-dirs) (= d-up maxdist)) "up")
        ((and (any? (lambda (x) (direction=? "left" x)) poss-dirs) (= d-left maxdist)) "left")
        ((and (any? (lambda (x) (direction=? "right" x)) poss-dirs) (= d-right maxdist)) "right")))))