Calculating powers of integers

Question

Is there any other way in Java to calculate a power of an integer?

I use Math.pow(a, b) now, but it returns a double, and that is usually a

Answer 1

There some issues with pow method:

1. We can replace (y & 1) == 0; with y % 2 == 0
   bitwise operations always are faster.

Your code always decrements y and performs extra multiplication, including the cases when y is even. It's better to put this part into else clause.

public static long pow(long x, int y) {
        long result = 1;
        while (y > 0) {
            if ((y & 1) == 0) {
                x *= x;
                y >>>= 1;
            } else {
                result *= x;
                y--;
            }
        }
        return result;
    }