1 aa* xaxaax (1,2) 2 (a*)(ab)*(b*) abc (0,2)(0,1)(?,?)(1,2) -2 (a*)(ab)*(b*) abc (0,2)(0,0)(0,2)(2,2) 3 ((a*)(ab)*)((b*)(a*)) aba (0,3)(0,2)(0,0)(0,2)(2,3)(2,2)(2,3) 4 (...?.?)* xxxxxx (0,6)(4,6) 5 (a|ab)(bc|c) abcabc (0,3)(0,2)(2,3) 6 (aba|a*b)(aba|a*b) ababa (0,5)(0,2)(2,5) 7 (a*){2} xxxxx (0,0)(0,0) 8 (a*)* a (0,1)(0,1) 9 (aba|a*b)* ababa (0,5)(2,5) 10 (a(b)?)+ aba (0,3)(2,3)(?,?) 11 .*(.*) ab (0,2)(2,2) 12 (a?)((ab)?)(b?)a?(ab)?b? abab (0,4)(0,1)(1,1)(?,?)(1,2)(?,?) -12 (a?)((ab)?)(b?)a?(ab)?b? abab (0,4)(0,1)(1,1)(?,?)(1,2)(2,4)