C:插入排序逻辑无法使用指针和结构来工作

Question

typedef struct record
{   
    char name[20];
    char surname[20];
    char telephone[20];

}Record;

typedef struct node
{
    Record data;
    struct node *next;
}Node;

Node *head = NULL;

/*
return positive value if *x > *y
return negative value if *x < *y
return 0 if *x == *y
*/
int cmpRecord(const Record* x, const Record* y) {
    if (x->name > y->name) return 1;
    if (x->name < y->name) return -1;
    return 0;
}

void addRecord(Record x)
{
    Node *previousNode = NULL;
    Node *newNode;
    Node *n;

    newNode = (Node*)malloc(sizeof(Node));
    newNode->data = x;
    newNode->next = NULL;

    if (head == NULL)  // The list is empty
    {
        head = newNode;
    }
    else       // The list is not empty
    {
        n = head;
        while (n->next != NULL)
        {
            if ((cmpRecord(&n->data.name, &newNode->data.name) < 0) && (cmpRecord(&n->next->data.name, &newNode->data.name) > 0)) // Insertion Sort
            {
                // We have to put it between these 2 nodes
                newNode->next = n->next;
                n->next = newNode;
                return;
            }

            else
            {
                previousNode = n;
                n = n->next;
            }
        }
            n->next = newNode;

     }

}

因此，这段代码应该在列表中添加人员记录，并根据名称按字母顺序对它们进行排序。但是，在显示列表时，项目不按字母顺序排列。似乎有什么问题？谢谢附言。 cmpRecord 在 if 语句中用于插入排序。

Answer 1

要按字母顺序比较两个字符串，请使用 strcmp():

int cmpRecord(const Record* x, const Record* y) {
    int cmp = strcmp(x->name, y->name);
    return (cmp > 0) - (cmp < 0);
}

并通过cmpRecord(&n->data, &newNode->data);调用此函数，因为data字段的类型为Record 。