How to make loop infinite with "x <= y && x >= y && x != y"?
java
Solution
You need two variables which are comparable, have the same value, but represent different instances, for example:
Integer x = new Integer(0);
Integer y = new Integer(0);
`x <= y` and `y <= x` are both true because the `Integer` are unboxed, however the instance equality `x == y` is false.
Note that it works with `Float`, `Long` and `Double` too, and any value (not just 0) works.
You can also play with the intricacies of your JVM - they generally cache integer up to 127 only, so this would work too:
Integer x = 128;
Integer y = 128;
(but it would not with 127).
Or more simply, since `Double`s are generally not cached at all:
Double x = 0d;
Double y = 0d;
Problem
I had this interview question some years ago but I haven't found the answer yet. What should be x and y to make a infinite loop? ``` while (x <= y&& x >= y && x != y) { } ``` We tried with `Nan`,`infinity+/-`,`null` `float` vs `int`.