C++的一个问题，求大佬相助，关于链表的一个问题

Question

部分代码如下：

typedef struct ElemType{
    char id[15];//ISBN     
    char name[50];//书名   
    char price;//定价
}ElemType;
typedef struct LNode {
    ElemType data; //数据域
    struct LNode *next; //指针域 
} LNode,*LinkList;
LNode *LocateElem(LinkList L, ElemType e) { //算法2.8 按值查找
    //在带头结点的单链表L中查找值为e的元素
    LNode *p;
    p=L->next;
    while(p&&p->data!=e){//[Error] no match for 'operator!=' (operand types are 'ElemType' and 'ElemType')
    p=p->next;
    }   
    return p;
} 
int main() {
    LinkList L;
    LNode *p,*q,*r;
    int i = 0, temp, a, c, choose,n;
    double price;
    ElemType e;
    cout << "3. 查找\n";
    choose = -1;
    while (choose != 0) {
        case 3: //链表的查找
            cout << "请输入所要查找价格:";
            cin >> price;
            r = LocateElem(L, price);
            if (r) {
                cout << "查找成功\n";
                cout << "该价格对应的书名为：" << r->data.name << endl << endl;
            } else
                cout << "查找失败！没有这个价格对应的书籍\n\n";
            break;
            }
    return 0;
}

报错：
[Error] no match for 'operator!=' (operand types are 'ElemType' and 'ElemType')

Answer 1

简单的来说，你没有在ElemType结构体中定义 !=，需要重载operator!=