main:
shared a1_ready := semaphore(0)
shared b1_ready := semaphore(0)
create_thread(thread_a)
create_thread(thread_b)
create_thread(thread_c)
thread_a:
statement a1
signal(a1_ready)
thread_b:
wait(a1_ready)
statement b1
signal(b1_ready)
thread_c:
wait(b1_ready)
statement c1