letter a z or A Z digit 0 1 2 3 4 5 6 7 8 9 or 0-9 sign + - Representing language tokens using regular expressions.
From here, Regular Expression ca (d+bca). So, after eliminating state q 2, we put a direct path from state q i to state q f having cost ca (d+bca) ca (d+bca). Regular Expression for no 0 or many triples of 0’s and many 1 in the strings. There is a path going from state q i to state q f via state q 2. Write regular expression to define language consisting of strings w such that, w contain atleast one 'a' followed by any number of 'b's followed by atleast one 'c'. Representing occurrence of symbols using regular expressions. Let us see the Regular Expression in compiler construction and automata theory. Turing Machine Comparison with Regular Expression, CFG, PDA and Deterministic Finite Automata More Examples of Regular Expression.