QP: Random shuffle

[QP]

I've used this algorithm for random shuffing;

Make array, Card(1, 2, ... ,n)
for i=0 to n{
Generate random number j
Swap Card(i) and Card(j)
}

But I got suspicious about this algorithm recently when i did a test for new game. Is it enough for completely random shuffle? Or does anyone know more powerful algorithm?

[Norm Wattenberger]

That will create a bias if j is a number between 0 and n.

for i = n - 1 to 1 step -1

j = rnd * (i + 1)

Swap cards(i), cards(j)
next

> I've used this algorithm for random shuffing;

> Make array, Card(1, 2, ... ,n)
> for i=0 to n{
> Generate random number j
> Swap Card(i) and Card(j)
> }

> But I got suspicious about this algorithm recently
> when i did a test for new game. Is it enough for
> completely random shuffle? Or does anyone know more
> powerful algorithm?

[QP]