join dfa

Question

iam not getting when to use cross product or union of dfa to  join two dfa can someone tell me

Answer 1

Yeah well! I can help you..

Suppose in a given string a's are divisible by 2 and/or b's divisible by 3 then to find product automata cross product of states of both automata should be done....

In both And opn and OR opn cross product should be done

Comments

bhai union ka nai btaya apne

Answer 2

you go for union when you have two possible language generated by grammar Suppose you have to Generate a language over {a,b}  having different input in initial as well as final..here first language starting with either a,b and end with a,b...i hope u got it...

and you go for cross product whenever two different language generated by grammar adding with either OR,NOT,AND...

Comments

design a dfa ending with 11 or  01  , union will work here but cross product will not