
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Bill goes to a donut shop to purchase exactly seven donuts. The shop offers four distinct kinds of donuts. Bill wants to buy at least one donut of each kind. How many different ways can Bill fulfill his order requirements?

Present the answer in LaTex format: \boxed{Your answer}
user