Thu, 23 Jun 2022 21:04:43 +0100 modified some proofs of s~>*
Chengsong [Thu, 23 Jun 2022 21:04:43 +0100] rev 551
modified some proofs of s~>*
(0) -300 -100 -30 -10 -1 +1 +10 +30 +100 tip