string1 has ends a1,a2, string2 has b1 b2; burn a1,a2,b1 when string1 burns out, that moment is 30 mins; start to burn b2 at this moment, it would take another 15mins, totaly it takes 45 mins to burn out both strings.
rootbear(啤酒晕头)
(#373537@0) Last Updated: 2002-2-19 This post has been archived. It cannot be replied.