Weird Java math execution

Question

I have an weird issue. I'm trying to store the result of an equation into a double variable.

double s = (((100 + 1)*(1/3))/100 + (1/3));

This returns a value a 0 rather than .67 (the correct value calculated from a calculator). Any reason why this could happen?

Note: A solution of saying that I could just make s = .67 is not a solution,

Thanks in advance.

Answer 1

The following uses integer (i.e. truncating) division, the result of which is zero:

1/3

To get floating-point division, turn either of the argument into a double, e.g.

1.0/3

Thus, the overall expression becomes:

double s = (((100 + 1)*(1./3))/100 + (1./3));

1. is the same as 1.0. Other ways to express the same number as a double are 1d and 1D.

The above expression evaluates to 0.6699999999999999.