You create your own Point class
This is an immutable class, and final (so you can safely use
instanceof in the equals method) and works out its hash code early (because you intend to use it in structures which use hash codes frequently). The hash code is worked out on the assumption that you will be using values between 0 and 100, and the % operators are so as to get more variability in the low-order part of the hash code. It is probably full of spelling errrors, but you will find them out when you get the compiler errors.
[pedantic mode]By the way, there is no such thing as a two-dimensional array in
Java, only an array of arrays.[/pedantic mode]