The Planner Module Flashcards
7 cards from real Picat practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 The Planner Module flashcards as text
Which directive correctly imports the Picat planner module?
Answer: import planner.
The correct syntax is `import planner.` placed at the top of the Picat source file.
What are the two user-defined predicates that the Picat planner module requires?
Answer: action/4 and final/1
The planner requires `action(State, NextState, Action, Cost)` and `final(State)` to be defined by the user.
What is the arity of the `action` predicate used in Picat's planner module?
Answer: 4
`action/4` takes four arguments: the current state, next state, the action term, and its cost.
What does the second argument of `plan/2` return after a successful call?
Answer: A list of action terms constituting the plan
`plan(State, Plan)` unifies Plan with a list of action terms that lead from State to a final state.
In `plan/4`, what does the second argument (Limit) represent?
Answer: An upper bound on the total resource cost
`plan(State, Limit, Plan, Cost)` uses Limit as an upper bound on the accumulated action costs, not raw depth.
What does the `final/1` predicate define in a Picat planning problem?
Answer: The goal condition that a state must satisfy for the plan to succeed
`final(State)` succeeds when State is a goal state, telling the planner when to stop searching.
Which default search strategy does Picat's planner module employ?
Answer: Iterative-deepening depth-first search
The planner uses iterative-deepening depth-first search (IDDFS) by default, progressively increasing the cost bound.