unsigned
myduck(unsigned a, unsigned b) {
	unsigned i;
	unsigned j = 2;		/* Accumulator */
	unsigned t1, t2;
	unsigned result = 0;

	for (i = 0; i < sizeof(a)*CHARBITS - 1; i++) {
		t1 = a % j;	/* Find current bits */
		t2 = b % j;
		a -= t1;	/* Strip lower bits */
		b -= t2;
		if (t1)
			if (t2) 
				result += j;
		j += j;
	}
	if (a)
		if (b)
			result += j;
}