//resultArray存储结果信息，currentMember存储当前入队的成员，A(n,m)
//(m<n),需要待排的数组
public void arrange(ArrayList<ArrayList> resultArray,ArrayList currentMember,int n, int m,int[] needToBeArranged)
{
//当数组大小为0时将存入currentMember中的信息添加到resultArray中
if(needToBeArranged.length == 0){
resultArray.add(currentMember);
return null;
}
boolean is2behand5 = false;
//从当前的n个元素中任意选择一个
for(int i = 0; i < currentMember.length; i ++)
{
if(currentMember[i] == 5)
{
for(int j = 0; j < currentMemeber.length; j ++)
if(currentMember[j] == 2){
is2behand5 = true;
break;
}
}
//如果2在5后面跳出本次循环
if(is2behand5 == true)
continue;
//添入当前元素
//这里一定不能是原来的数组，因为java存储的是引用
ArrayList currentMemberClone = currentMember.clone();
currentMemberClone.add(currentMember[i]);
//将剩余元素的数组把currentMember[i]剔除
int mm[] = new int[needToBeArranged - 1];
for(int j = 0; j < i- 1; j ++)
{
mm[j] = needToBeArranged[j];
}
for(int j = i; j < needToBeArranged.length; j ++)
{
mm[j - 1] = needToBeArrayged[j];
}
//递归排列其余A(n-1,m-1)
arrange(currentMemberClone,currentMember,n-1,m-1,needToBeArranged);
//最终的排列结果存入resultArray中，与返回值无关
return null;
}//end for
}