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Computer Science

Size of array after resizing?

I do not understand how the size of the array after resizing is 8. How do you come to this conclusion?

ArrayBag b = new ArrayBag();
for (int i = 1; i <= 18; i++) {
   b.add(i);
}
for (int i = 1;  i <= 15; i++) {
   b.remove(i);
}

1 Answer

Steven Parker
Steven Parker
229,005 Points

They're talking about the storage size, and not the number of active elements. You didn't provide a link to the course page, but it should have told you about how space is not allocated (or de-allocated) on a per-item basis, but in clusters that are powers of 2 in size. So when you get down to 3 items, the last allocation threshold was 4, and with de-allocations retaining double the size in use, that would make 8.