Question

Give an informal description of a pushdown automaton that recognizes the language in Exercise 2.9.

Short answer

Answer:

Informal description of the pushdown automaton that recognizes the language $A=\{a^j{b}^j{c}^{k}i=jorj=kwherei,j,k\ge 0\}$can be given.

Step-by-step solution

Explain pushdown automaton

Pushdown Automaton write symbols on the stack and read them. Writing a new symbol pushes down all the symbols in the stack before.

Give an informal description of a pushdown automaton that recognizes the language A.

Informal description of the pushdown automaton that recognizes the language $A=\left\{a^j{b}^j{c}^k\right|i=jorj=kwherei,j,k\ge 0\}$is as follows,

1. Nondeterministic, branching to step 2 or 6.
2. Read and push a ’s.
3. Pop a’s, and read b ’s.
4. If stack is empty,accept.
5. Skip a’s and c’s input.
6. Push b’s
7. Read c’s.
8. When stack is empty and c’s finish, accept.

Therefore, the informal description has been given