context-free-grammar

I'm studying for my computing languages test, and there's one idea I'm having problems wrapping my head around. I understood that regular grammars are simpler and cannot contain ambiguity, but can't do a lot of tasks that are required for programming languages. I also understood that context-free grammars allow ambiguity, but allow for some things necessary for programming languages (like palindromes). What I'm having trouble with is understanding how I can derive all of the above by knowing that regular grammar nonterminals can map to a terminal or a nonterminal followed by a terminal or that

Given: I have no idea what the accepted language is. From looking at it you can get several end results: 1.) bb 2.) ab(a,b) 3.) bbab(a, b) 4.) bbaaa Grijesh Chauhan How to write regular expression for a DFA In any automata, the purpose of state is like memory element. A state stores some information in automate like ON-OFF fan switch. A Deterministic-Finite-Automata(DFA) called finite automata because finite amount of memory present in the form of states. For any Regular Language(RL) a DFA is always possible. Let's see what information stored in the DFA (refer my colorful figure). ( note: In

I am new to CFG's, Can someone give me tips in creating CFG that generates some language For example L = {a m b n | m >= n} What I got is: S o -> a | aS o | aS 1 | e S 1 -> b | bS 1 | e but I think this area is wrong, because there is a chance that the number of b 's can be greater than a 's. Grijesh Chauhan How to write CFG with example a m b n L = {a m b n | m >= n}. Language description: a m b n consist of a followed by b where number of a are equal or more then number of b . some example strings: {^, a, aa, aab, aabb, aaaab, ab......} So there is always one a for one b but extra a are