Suppose you are constructing a finite-state machine for entering a security code into an automatic teller machine (ATM). The following rules are implemented. i. A user enters a string of four digits, one digit at a time. ii. If the user enters the correct four digits of the password, the ATM displays a welcome screen iii. When the user enters an incorrect string of four digits, the ATM displays a screen that informs the user that an incorrect password was entered. iv. If a user enters the incorrect password three times, the account is locked. Answer the following questions. 1. What is the input alphabet for this machine? 2. What is the output alphabet for this machine? 3. Draw the FSM clearly identifying all states, including start state and end state(s).
