(define rank 0)
(define max-size 0)
(define biggest-purchase #f)
(map (lambda(x) 
	(let ((sz (collection-vertex-size (vertices x))))
		(display sz)
		(cond ((> sz max-size) (set! max-size sz) 
				       (set! biggest-purchase x)
				       (set! rank (edge-rank x h2))))
		(describe x))) (set-edge->list (edges h2)))