C语言 链表 A 与另一个与 A 关联的 B 相关联

Question

//2 个由指针绑定的结构

 struct A_cust            // customer information, a double-linked list with another pointer
   {
    char cust_info [20];  // as an example
    A_cust *prevCust;     // prev customer record
    A_cust *nextCust;     // next customer record
    B_tran *point_to_B;   // to the list of transaction records
   };
 struct B_tran            // transaction records, a double-linked list with another pointer
   {
    char cust_tran [20];  // as an example
    B_tran *prevTran;     // prev customer transaction
    B_tran *nextCust;     // next customer transaction
    A_cust *point_to_A    // to the list of customer records
   };

编译器在解析"A_cust"时不知道"B_tran"如果我把"B_tran"的定义放在第一位，那么编译器就不知道"A_cust"是什么

任何想法，欧内斯特

Answer 1

在代码顶部添加以下声明

struct B_tran;

编辑：这称为前向声明，您向编译器承诺稍后将定义B_tran。（感谢格雷格）