Unformatted text preview: l in to at most l ! classes. For 1 â‰¤ i â‰¤ ( l !), let z i be the shortest string in L such that  z i  â‰¥ l, and  z i  âˆ’ l â‰¡ i mod ( l !) . Notice that for some i , there might not exists some z i that satisfy above equation. We use S to denote the set that contains all the i such that z i exists. Now we can write L by the following regular expression, L = { x   x  â‰¤ l,x âˆˆ L } âˆª Â± i âˆˆ S z i ( a ( q !) ) * . 1...
View
Full Document
 Spring '09
 EdmundM.Clarke
 Formal languages, Regular expression, Regular language, bonus problem

Click to edit the document details