roll(int n)
{
    int i, j;

    i = (RAND_MAX / n) * n;
    while ((j = rand()) >= i)
	continue;
    return (j % n);
}
roll(int n)
{
    int i, j;

    i = (RAND_MAX / n) * n;
    while ((j = rand()) >= i)
	continue;
    return (j % n);
}