Stack of integer array push operation

Question

I have declared a stack of integer array -

Stack<int[]> stack = new Stack<int[]>();

When I am pushing an object to stack using following code, I am getting an error -

stack.push({0,0});

But it works when I use the following code -

stack.push(new int[]{0,0});

So I am bit confused why the first way did not work. Does {0,0} not declare a new array object which can be pushed on the stack?

Your intuition was correct. In Java, you need to be specific about everything. — jkeuhlen, Aug 03 '15 at 20:27

score 2 · Accepted Answer · answered Aug 03 '15 at 20:27

Just using the braces {0,0} doesn't by itself create and initialize a new array. You may be confused by the following syntax that makes this look like it's possible.

int[] someArray = {0, 0};

This syntax allows just the braces, and not the new int[] before it, only when it's part of a declaration. You don't have a declaration, so it's invalid syntax. Without a declaration, the new int[] part is required.

score 1 · Answer 2 · edited May 23 '17 at 10:26

1

Try this:

stack.push(new int[] {0,0});

or,

int[] array = {0, 0} // creates a new array
stack.push(array);

Because, only {0, 0} does not create any new array, that's why you get errors. Read more.

edited May 23 '17 at 10:26

Community

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answered Aug 03 '15 at 20:29

rakeb.mazharul

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Stack of integer array push operation

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