// ab_b_all.dfa  a simple DFA  accepts tape
// regular expression (a+b)* b  accepts b  abab   aaab   bbbb
// any string of a's and b's that ends in b

start q1
final q2

q1  a  q1
q1  b  q2
q2  a  q1
q2  b  q2

enddef

tape  aabbaaabbbab
tape  b
tape  ab
tape  abb
tape  aab
tape  a    // reject
tape  ba   // reject
tape  abcb // reject no transition to c