Use the example in the picture and do it like that. Thanks Vending Machine Symbolic State Diagram

Each state represents how much money has been deposited

Variables:

$N=$ nickel, $10$ detected

$D=$ dime, $5$ detected

$R=$ release

Provide a design of the sequential circuit for the vending machine controller:

One product sells for $$0\mathrm{.}40,$ and the machine takes only quarters $($input Q$)$ and dimes

$($input D$)$ with an output signal I for product release and a few necessary output signals

for change release $($if there is change to return$),$ for example, C$5$ for a $5-$cent change, C$10$

for a $10-$cent change, etc.. No other signals are used.

$($a$)$ Show the complete state diagram and state transition table.

$($b$)$ How many flip$-$flops are needed? Draw a block diagram of the circuit showing the

key blocks, signals, and wires.

$($c$)$ How many K$-$maps are needed to derive the complete circuit?Vending Machine Symbolic State Table