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115 | main:
shared agent_sem := semaphore(1)
shared match := semaphore(0)
shared paper := semaphore(0)
shared tobacco := semaphore(0)
shared mutex := semaphore(1)
shared is_match := false
shared is_paper := false
shared is_tobacco := false
shared match_ready := semaphore(0)
shared paper_ready := semaphore(0)
shared tobacco_ready := semaphore(0)
create_thread(agent)
create_thread(smoker_with_matches)
create_thread(smoker_with_paper)
create_thread(smoker_with_tobacco)
create_thread(pusher_match)
create_thread(pusher_paper)
create_thread(pusher_tobacco)
agent:
create_thread(agent_without_matches)
create_thread(agent_without_paper)
create_thread(agent_without_tobacco)
agent_without_matches:
while true do
wait(agent_sem)
signal(paper)
signal(tobacco)
agent_without_paper:
while true do
wait(agent_sem)
signal(match)
signal(tobacco)
agent_without_tobacco:
while true do
wait(agent_sem)
signal(match)
signal(paper)
smoker_with_matches:
while true do
wait(match_ready)
make_cigarette()
signal(agent_sem)
smoke()
smoker_with_paper:
while true do
wait(paper_ready)
make_cigarette()
signal(agent_sem)
smoke()
smoker_with_tobacco:
while true do
wait(tobacco_ready)
make_cigarette()
signal(agent_sem)
smoke()
pusher_match:
while true do
wait(match)
wait(mutex)
if is_paper then
is_paper := false
signal(match_ready)
else if is_tobacco then
is_tobacco := false
signal(tobacco_ready)
else
is_match := true
signal(mutex)
pusher_paper:
while true do
wait(paper)
wait(mutex)
if is_match then
is_match := false
signal(paper_ready)
else if is_tobacco then
is_tobacco := false
signal(tobacco_ready)
else
is_paper := true
signal(mutex)
pusher_tobacco:
while true do
wait(tobacco)
wait(mutex)
if is_match then
is_match := false
signal(paper_ready)
else if is_paper then
is_paper := false
signal(match_ready)
else
is_tobacco := true
signal(mutex)
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