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Best way of implementing a queue's isEmpty() method
You have a queue called someQ
There are two ways to find out if the queue is empty()
head == null;orsize() == 0;
size == 0;
where size() is determined by the number of elements enqueued onto the queue by incrementing a global variable called.size
Which is the best method and why?
Last edited by pyler; April 6th, 2014 at 10:28 PM.
Re: Best way of implementing a queue's isEmpty() method
invalid syntax, Queue is an interface so you cannot use the new key word in java to make a new object of it.You have some Queue<E> someQ = new Queue<E>()
if you are determining the size, then use the size() method.
comparing head == null is an alternative since peek, peekFirst method returns a null when the array is empty, but I think that is not 100% accurate. why?
what if I have a Queue of String generic. and I pushed these values:
"me"
"you"
null
the top of stack in Queue is null so if you are determining if the Queue is empty using head == null, then you can conclude that the above Queue is empty, but actually not, it returns a null just because its top of stack is null, but actually it has 3 elements.
pyler (April 6th, 2014)
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