How to find duplicate Bitmaps in a list of objects?

Question

Java

There is a large array of Bitmap objects. You need to go through each element and create a separate list where each duplicate will be sorted. For example, three identical bitmaps will go in order, even if the last duplicate was at the end of the list.
For comparison, the Bitmap.sameAs(anotherBitmap) method is used.
How can I iterate over an array in such a way that there is a minimum time cost.