Hint for Section 7.2 Question 1

1. For this finite-state automaton:

• the set of inputs is 5, 10 and 20 cents;
• the set of states is "0 cents deposited", "5 cents deposited", "10 cents deposited", "15 cents deposited" and "20 or more cents deposited";
• the initial state is "0 cents deposited";
• the accepting state is "20 or more cents deposited";
• the next state function is the sum of the present state and the next coin input.

When you are drawing the transition diagram, use a circle for each state, with a double circle for the accepting state. Use the inputs to label the arrows which connect the states.

Back to Section 7.2
Full solution