b : bool b = 0
i : int i = 0
event queue:
check queue:
	time	eid	pid	event
	0	0	1	null
b : bool b = 0
i : int i = 0
event queue:
check queue:
	time	eid	pid	event
	10	1	0	
b : bool b = 0
i : int i = 0
event queue:
check queue:
	time	eid	pid	event
	20	2	0	i := 13
	20	3	0	b := true
b : bool b = 0
i : int i = 13
event queue:
check queue:
	time	eid	pid	event
	20	3	0	b := true
	30	4	0	
b : bool b = 1
i : int i = 13
event queue:
check queue:
	time	eid	pid	event
	30	4	0	
	30	4	0	
time: 20
queue should be contain only null (join) event here 
event queue:
check queue:
	time	eid	pid	event
	30	4	0	
	30	4	0	
now queue should be empty 
event queue:
check queue:
	(empty)
time: 30
