The practice of the Compiler course.
It will transfrom the regex expression into a corresponding table. And in this procedure, it will transfrom into a NFA and then a DFA first. The form of table is like this:
StartState 0
EndState 2
Table
a b c d ...
0 | 1 -1 1 0 ...
1 | 2 -1 2 1 ...
2*| 0 1 -1 -1 ...