a a a a a
1 2 1 2 1 2
aaaaa is not accepted
b b b b b
1 3 3 3 3 3
bbbbb is accepted
a b a b a
1 2 2 1 3 2
ababa is not accepted
b a b a b
1 3 1 3 1 3
babab is accepted
a b b b b
1 2 2 2 2 2
abbbb is not accepted
1. Problem 2.1 (b), page 62.
Each string is shown spaced out so that the state of the DFA after reading
each letter can be shown between that letter and the next.
a a a a a
1 2 1 2 1 2
aaaaa is not accepted
b b b b b
1 3 3 3 3 3
bbbbb is accepted
a b a b a
1 2 2 1 3 2
ababa is not accepted
b a b a b
1 3 1 3 1 3
babab is accepted
a b b b b
1 2 2 2 2 2
abbbb is not accepted
1. Problem 2.1 (b), page 62.
Each string is shown spaced out so that the state of the DFA after reading
each letter can be shown between that letter and the next.
a b b a b
1 1 2 3 2 3
abbab is not accepted
b a b b a
1 2 3 1 2 3
babba is not accepted
a b b a a
1 1 2 3 2 3
abbaa is not accepted
b b a a b
1 2 3 2 3 1
bbaab is not accepted
a b a a a
1 1 2 3 2 3
abaaa is not accepted
1. Problem 2.1 (c), page 62.
Each string is shown spaced out so that the state of the DFA after reading
each letter can be shown between that letter and the next.
a b c
1 2 3 1
abc is not accepted
b c a c b a
1 3 1 2 4 3 2
bcacba is accepted
c c c a
1 1 1 1 2
ccca is accepted
c b a b c
1 1 3 2 3 1
cbabc is not accepted
b
1 3
b is not accepted
b b b b
1 3 4 3 4
bbbb is accepted