Often big numbers become negative

Question

Since I started using eclipse for project euler, I noticed that big numbers sometime become a seemingly random negative numbers. I suppose this has something to do with pass

Answer 1

In mathematics numbers are infinite. However in computers they are not. There is MAX_VALUE for each int-like type: int, short, long. For example Integer.MAX_VALUE. When you try to increase number more than this value the number becomes negative. This way the internal binary representation of numbers work.

int i = Integer.MAX_VALUE;
i++; // i becomes negative.