How to sort three variables using at most two swaps?

Question

The following algorithm can sort three variables x, y and z of type K which are comparable using operator<

Answer 1

void sort(int& a, int& b, int& c)
{
   swap(a, min(a, min(b, c)));
   swap(b, min(b, c));
}

2 swaps, 3 comparisons.