String Acceptance
1. **Problem Statement:** Determine if the strings "ababbaaa" and "abaa" are accepted or rejected by the given automata A, B, and C.
2. **Understanding the Automata:** Each automaton has states and transitions labeled with letters a and b. A string is accepted if there exists a path from the start state to a final state following the string's letters.
3. **Assumptions:** Since final states are not explicitly given, we assume all states are accepting states for this problem or that acceptance depends on reachability.
4. **Check String I: "ababbaaa"**
- For Automaton A:
- Start at state 1.
- Read 'a': 1 → 2 (a)
- Read 'b': 2 → 3 (b)
- Read 'a': 3 has no outgoing 'a' edge, but from 2 → 4 (a,b) and 4 → 3 (a), so try 2 → 4 → 3 path.
- However, after reading 'b' at 2 → 3, no 'a' from 3.
- Try alternative path: 1 → 4 (a,b) on 'a', then 4 → 3 (a) on 'a'.
- The string does not fit the transitions exactly; thus, likely rejected.
- For Automaton B:
- Start at 1.
- 'a': 1 → 2 (a,b)
- 'b': 2 → 4 (a)
- 'a': 4 → 2 (a)
- 'b': 2 → 4 (a)
- 'b': 4 → 2 (a)
- 'a': 2 → 4 (a)
- 'a': 4 → 2 (a)
- 'a': 2 → 4 (a)
- The string can be followed by alternating between 2 and 4 states.
- Accepted.
- For Automaton C:
- Start at 1.
- 'a': 1 → 2 (a,b)
- 'b': 2 → 5 (a,b)
- 'a': 5 → 6 (a,b)
- 'b': 6 has no outgoing edges.
- String cannot be fully processed.
- Rejected.
5. **Check String II: "abaa"**
- Automaton A:
- 1 → 2 (a)
- 2 → 3 (b)
- 3 no 'a' edge, but 1 → 4 (a,b) and 4 → 3 (a) exist.
- String does not fit transitions fully.
- Rejected.
- Automaton B:
- 1 → 2 (a,b)
- 2 → 4 (a)
- 4 → 2 (a)
- 2 → 4 (a)
- Accepted.
- Automaton C:
- 1 → 2 (a,b)
- 2 → 3 (a)
- 3 → 6 (a,b)
- 6 no outgoing edges for next 'a'.
- Rejected.
**Final answers:**
- String "ababbaaa": Accepted by B, Rejected by A and C.
- String "abaa": Accepted by B, Rejected by A and C.