free(stk)不就释放栈了吗？为什么在之前还要有free(stk->data)？

Question

Stack* Stack_Create(int maxlen)
// 创建栈
{
    Stack* stk = (Stack*)malloc(sizeof(Stack));
    stk->data = (T*)malloc(sizeof(T)*maxlen);
    stk->max = maxlen;
    stk->top = -1;
    return stk;
}

void Stack_Free(Stack* stk)
// 释放栈
{
    free(stk->data);
    free(stk);
}