從不兼容的指針類型/ deref指向不完整類型的指針

Question

我有這個二叉樹，其中每個結構，讓我們調用它們A有另一個結構類型的指針，讓我們調用它們B，指向另一個結構類型B等等形成一個結構類型B）的鏈表。

圖片：

(A) 
/\ 
(A)->(B)->(B)->(B)->|| 

的問題，我不知道。我收到一個錯誤，指出：

AddRemove.c: In function ‘AddRemove’: 
AddRemove.c:21: warning: assignment from incompatible pointer type 
AddRemove.c:22: error: dereferencing pointer to incomplete type 
AddRemove.c:23: error: dereferencing pointer to incomplete type 
AddRemove.c:24: error: dereferencing pointer to incomplete type 
AddRemove.c:26: error: dereferencing pointer to incomplete type 

代碼：

struct A{ 
//other variables 
struct A *left,*right; 
struct B *queue;   
}*rootT; 

struct B{ 
//other variables 
struct B *next; 
}; 

void AddRemove(struct A *aNode, struct B *bNode){ 
/*aNode is the memory location of the struct node (A) in the picture and bNode is 
a struct node that we want to add to the linkedlist.*/ 
struct B *Bptr; //Used to go through the linkedlist of struct type B 
if(aNode->queue==NULL){ /*If the pointer of node (A) is null then we have the 
pointer point to bNode, the node that we wanted to add.*/ 
    aNode->queue=bNode; 
    bNode->next=NULL; 
} 
else{ 
    Bptr=aNode->queue; /*Otherwise have the temp pointer point to what 
node (A)'s pointer points to, which should be the first struct type (B)*/ 
    while(Bptr->next!=NULL){ /*Keep pointing to the next struct of type B until 
we hit the end*/ 
     Bptr=Bptr->next; 
    } 
    Bptr->next=bNode; 
} 
} 

Answer 1

缺少分號：

struct B{ 
    //other variables 
    struct B *next; 
}; 
^ 

此外，由於您使用的是結構的定義裏面不完全類型，你應該使用typedef：

typedef struct A A; 
typedef struct B B; 

struct A { 
    //other variables 
    A *left,*right; 
    B *queue;   
} *rootT; 

struct B { 
    //other variables 
    B *next; 
};