有错误D:尀计算机1班尀sy7.3.c(11) : error C2143: syntax error : missing ✀)✀ before ✀&✀

#include
#include
#define MaxSize 100
typedef char ElemType;
typedef struct node
{
ElemType data;
struct node * lchild;
struct node * rchild;
}BTNode;
void CreateBTNode(BTNode * &b,char * str)
{
BTNode * St[MaxSize],* p=NULL;
int top=-1,k=1,j=0;
char ch;
b=NULL;
ch=str[j];
while(ch!='\0')
{
switch(ch)
{
case'(':top++;St[top]=p;
break;
case')':top--;
break;
case',':k=2;
break;
default:p=(BTNode *)malloc(sizeof(BTNode));
p->data=ch;
p->lchild=p->rchild=NULL;

if(b==NULL)
{
b=p;
}
else
{
switch(k)
{
case 1:St[top]->lchild=p;
break;
case 2:St[top]->rchild=p;
break;
}
}
}
j++;
ch=str[j];
}
}