context-free-grammar,automaton,pushdown-automaton

The set of context-free languages (or PDAs) is not closed under complementation. (There's a simple demonstration in the answer to What is the context free grammar for the complement of the double word over 0,1?, which constructs a CFG for the complement of {ww|w∈{0,1}*}. The fact that {ww|w∈{0,1}*} is not...

finite-automata,automata,pda,pushdown-automaton,automata-theory

Of course, every state can be final in a deterministic pushdown automaton. Your approach seems correct to me. Depending on your definition on determinism it might be necessary to also add a transition that deals with the case where you read a 0 in state q_1 in order to have...

parsing,recursion,compiler-construction,automata,pushdown-automaton

Firstly,you'll need to remove left-recursion leading to S -> cAd A -> aA' A' -> bA' | epsilon Then, you can calculate FIRST(A) = a // as a is the only terminal nderived first from A. EDIT :- For your second question, S -> AS' S' -> AS' | epsilon...

context-free-grammar,pushdown-automaton,context-free-language

Using intuition is a valuable technique. As you solve more such problems, your intuitions sharpen, so it gets easier. There's no formal technique to convert a description of a language into a CFG (unless the description is something which maps onto CFGs, of course, like a set of production rules)....