Your Name
CS 4301
Lab 11
{(x=, x=ans) | x is in {a, b}* and
               ans = 1 if x has a substring of length four that
                     begins and ends with the same symbol
               ans = 0 otherwise}

Input:  aab=
Output:            aab=0

Input:  aba=
Output:            aba=0

Input:  baa=
Output:            baa=0

Input:  babab=
Output:            babab=0

Input:  aabbb=
Output:            aabbb=0

Input:  bbbaa=
Output:            bbbaa=0

Input:  abbba=
Output:            abbba=0

Input:  aabbbbb=
Output:            aabbbbb=1

Input:  bbbbbbbaa=
Output:            bbbbbbbaa=1

Input:  bbbabbbabbb=
Output:            bbbabbbabbb=1

Input:  =
Output:            =0

Input:  a=
Output:            a=0

Input:  b=
Output:            b=0

Input:  aa=
Output:            aa=0

Input:  ab=
Output:            ab=0

Input:  ba=
Output:            ba=0

Input:  bb=
Output:            bb=0

Input:  aaa=
Output:            aaa=0

Input:  baa=
Output:            baa=0

Input:  aba=
Output:            aba=0

Input:  bbb=
Output:            bbb=0

Input:  abba=
Output:            abba=1

Input:  baba=
Output:            baba=0

Input:  babba=
Output:            babba=1

Input:  abbbba=
Output:            abbbba=1

Input:  bbabababa=
Output:            bbabababa=1

Input:  bbaaaabaaa=
Output:            bbaaaabaaa=1

Input:  babaaabaaa=
Output:            babaaabaaa=1

Input:  abaaaaaaaaaaa=
Output:            abaaaaaaaaaaa=1

Input:  bababaabababa=
Output:            bababaabababa=1