c++编写放大器时赋值报错

c++编写放大器，将结点值放入N的时候报错
typedef struct element
{
char N;
int D;
int d;
bool boost;
}element;
//定义二叉树
typedef struct bitnode
{
struct element data;
bitnode lchild, * rchild;
}bitnode, * bitTree;

//创建二叉树
void createbitTree(bitTree &T)
{
char c;
int a;
c = getchar();
if (c == '#')T = nullptr;
else
{
scanf_s("%d", &a);
T = (bitnode*)malloc(sizeof(bitnode));
if(T ==nullptr)exit(-1);
T->data->N = c;
T->data->d = a;
T->data->boost = false;
T->data->D = 0;
T->lchild = T->rchild = nullptr;
createbitTree(T->lchild);
createbitTree(T->rchild);
}

}

请大家帮帮忙到底哪里有问题

T = (bitnode*)malloc(sizeof(bitnode)); 分配了 sizeof(bitnode) 大小的内存，但是它的 struct element *data;并没有分配内存，


typedef struct bitnode
{
struct element data; //不是指针则调用方式是T->data.N = c;
bitnode lchild, * rchild;
}bitnode, * bitTree;