有N 个序号:0, 1, 2... N-1
其全排序有N!种
如何用简单的办法生成全部排序?

static int[] a = ...{0,1,2,3,4,5};
static int n = 6;

static void swap(int arg1, int arg2)

...{
int temp;
temp = a[arg1];
a[arg1] = a[arg2];
a[arg2] = temp;
}
static void sort(int index)

...{
int i;

if (index == n)

...{
for (i = 0; i < n; i++)

...{
System.out.print(a[i]);
System.out.print(" ");
}
System.out.println("");
return;
}
for (i = index; i < n; i++)

...{
swap(index,i);
sort(index + 1);
swap(index,i);
}
}