How can “while (i == i) ;” be a non-infinite loop in a single threaded application?

Question

I just got a question that I can\'t answer.

Suppose you have this loop definition in Java:

while (i == i) ;

What is the type of

Answer 1

I would add

float i = Float.NaN;

as well as

double i = Double.NaN;

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A common trick in these sort of questions it in the assumption you make that i is an int. Other common assumptions might be s is a String, x,y are a double, ch is a char, b is a byte etc. If you see a question like this you can bet that 'i' is not its expect type.

A similar question is; This never loops, what is 'x'

while(x == x && x != x + 0) { }

Another question I quite like is; This loop is an infinite loop, what are the possible values of x. (: I count twelve of them :)

while(x != 0 && x == -x) { }