The key to why the obvious algorithm of "half a Fisher-Yates shuffle" isn't enough is that it uses O(k) memory, whereas Vitter's algorithm is constant. http://

The key to why the obvious algorithm of "half a Fisher-Yates shuffle" isn't enough is that it uses O(k) memory, whereas Vitter's algorithm is constant. http://play.golang.org/p/UqC6XWrPLB http://play.golang.org/p/UqC6XWrPLB