6-5 链式表操作集 (20分)

注意操作失败时输出信息的输出格式

Position Find( List L, ElementType X ){
    while(L){
        if (L->Data == X){
            return L;
        }
        L = L->Next;
    }
    return ERROR;
}
List Insert( List L, ElementType X, Position P ){
    List node = (struct LNode *)malloc(sizeof(struct LNode));   //待插入的结点
    node->Data = X;
    node->Next = NULL;
    
    if (L == P){            //插在头结点前面
        node->Next = L;
        return node;
    }
    
    List p = L;             //通过p操作L链表
    while(p){
        if(P == p->Next){    //若满足条件，此时p指向P的前一个结点
            node->Next = p->Next;
            p->Next=node;
            return L;
        }
        p = p->Next;
    }
                              //没插入成功
    printf("Wrong Position for Insertion\n");
    return ERROR;
    
}
List Delete( List L, Position P ){
    if (L == P){
        L = L->Next;
        return L;
    }
    List p = L;
    while(p){
        if (P == p->Next){      //若满足条件，此时p指向P的前一个结点
            p->Next = P->Next;  
            free(P);
            return L;
        }
        p = p->Next;
    }
    //没删除成功
    printf("Wrong Position for Deletion\n");
    return ERROR;
}

Position Find( List L, ElementType X ){
    while(L){
        if (L->Data == X){
            return L;
        }
        L = L->Next;
    }
    return ERROR;
}
List Insert( List L, ElementType X, Position P ){
    List p = L, temp, node;
    node = (List)malloc(sizeof(struct LNode));
    node->Data = X;
    if (L == P){            //插在头结点前面
        node->Next = L;
        return node;
    }
    while(p){
        if (p->Next == P){
            node->Next = p->Next;
            p->Next = node;
            return L;
        }
        p = p->Next;
    }
    printf("Wrong Position for Insertion\n");       //一定注意换行，唯独你没懂。。。
    return ERROR;
}
List Delete( List L, Position P ){
    if (L == P){        //删除第一个结点
        L = L->Next;
        return L;
    }
    List p = L;
    while(p){
        if (p->Next == P){
            p->Next = P->Next;
            return L;
        }
        p = p->Next;
    }
    printf("Wrong Position for Deletion\n");
    return ERROR;
}