All you need to know is that Set doesn't allow duplicates in Java. Which means if you have added an element into Set and trying to insert duplicate element again, it will not be allowed. In Java, you ...

You have been given an integer array/list (ARR) of size N which contains numbers from 0 to (N - 2). Each number is present at least once. That is, if N = 5, the array/list constitutes values ranging ...