How to reference the highest index in an Array?

Question

public LibraryClass(int x) {
    bookShelf = new TextBook[x];
    for(int i=0;i<x;i++){
        bookShelf[i] = new TextBook("textbook" + i, 5);
    }
    nextBook = x - 1;  
    }

So this is my code, and whatever input we give the int x, for example 5, the max index would be 4. i could easily yes put a pointer on this position, but is there any other code which gives me the highest index number (NOT the highest element) to me?

Since you surely mean the "highest index number with an `TextBook` instance" you should write that in your question. Btw, prefer a `List` instead. — Tom, Nov 03 '15 at 12:35

score 3 · Answer 1 · answered Nov 03 '15 at 12:32

int highest =  bookShelf.length -1;

Will give the result which is the highest index of array.

The reason for doing -1 is array indices starts from zero. Hence the 5 indices array length will be 6.

It seems you are looking for next and previous navigations, hence you might want to look at the data structure LinkedList

score 1 · Answer 2 · answered Nov 03 '15 at 12:32

1

The highest index of an array is always array.length - 1 (or bookShelf.length - 1 in your specific example).

answered Nov 03 '15 at 12:32

Eran

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score 0 · Answer 3 · edited May 23 '17 at 12:03

0

Just to repeat what others have said, use

array.length - 1

to get the highest index in the array. Or, given your example,

x - 1

To expand on what others have said, see this SO question for more info on arrays and of course the documentation for more functions on arrays.

edited May 23 '17 at 12:03

Community

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answered Nov 03 '15 at 12:35

Arc676

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How to reference the highest index in an Array?

3 Answers3