MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
	THREAD 1 - start of loop
	THREAD 1 - calling P
	THREAD 1 - inside critical section
		THREAD 2 - start of loop
		THREAD 2 - calling P
			THREAD 3 - start of loop
			THREAD 3 - calling P
				THREAD 4 - start of loop
				THREAD 4 - calling P
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
	THREAD 1 - leaving the critical section
	THREAD 1 - start of loop
	THREAD 1 - calling P
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
		THREAD 2 - inside critical section
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
		THREAD 2 - leaving the critical section
		THREAD 2 - start of loop
		THREAD 2 - calling P
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
			THREAD 3 - inside critical section
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
			THREAD 3 - leaving the critical section
			THREAD 3 - start of loop
			THREAD 3 - calling P
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
				THREAD 4 - inside critical section
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
				THREAD 4 - leaving the critical section
				THREAD 4 - start of loop
				THREAD 4 - calling P
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
	THREAD 1 - inside critical section
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD
MAIN THREAD


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