curriculum/challenges/english/blocks/workshop-breadth-first-search/68da6138d70960c197ec5ef2.md
If the current string isn't complete yet, you need to explore the next possible states. Add an else clause to your if statement.
Inside the else block, you'll handle adding opening parentheses. Add an if statement to check if opens_used < pairs. This ensures you don't use more opening parentheses than allowed.
If this condition is true, append a new tuple to the queue: (current + '(', opens_used + 1, closes_used). This represents the state after adding an opening parenthesis.
You should have an else clause for your if statement inside the while loop.
({ test: () => runPython(`
assert _Node(_code).find_function("gen_parentheses").find_whiles()[0].find_bodies()[0].find_ifs()[0].tree.orelse
`) })
You should have an if statement inside the else block checking if opens_used < pairs.
({ test: () => runPython(`
assert _Node(_code).find_function("gen_parentheses").find_whiles()[0].find_bodies()[0].find_ifs()[0].find_conditions()[1].is_equivalent("opens_used < pairs")
`) })
You should append (current + '(', opens_used + 1, closes_used) to the queue when the condition is true.
({ test: () => runPython(`
assert _Node(_code).find_function("gen_parentheses").find_whiles()[0].find_bodies()[0].find_ifs()[0].find_bodies()[1].has_call("queue.append((current + '(', opens_used + 1, closes_used))")
`) })
def gen_parentheses(pairs):
if not isinstance(pairs, int):
return 'The number of pairs should be an integer'
if pairs < 1:
return 'The number of pairs should be at least 1'
queue = [('', 0, 0)]
result = []
--fcc-editable-region--
while queue:
print(queue)
current, opens_used, closes_used = queue.pop(0)
if len(current) == 2 * pairs:
result.append(current)
--fcc-editable-region--
return result
print(gen_parentheses(1))