用c实现两个有序链表序列的合并

以下是C语言实现两个有序链表序列合并的示例代码：

#include <stdio.h>
#include <stdlib.h>

struct Node {
    int data;
    struct Node* next;
};

struct Node* mergeLists(struct Node* head1, struct Node* head2) {
    struct Node* mergedList = NULL;
    struct Node** tailRef = &mergedList;

    while (1) {
        if (head1 == NULL) {
            *tailRef = head2;
            break;
        } else if (head2 == NULL) {
            *tailRef = head1;
            break;
        }

        if (head1->data <= head2->data) {
            *tailRef = head1;
            head1 = head1->next;
        } else {
            *tailRef = head2;
            head2 = head2->next;
        }

        tailRef = &((*tailRef)->next);
    }

    return mergedList;
}

void printList(struct Node* head) {
    while (head != NULL) {
        printf("%d ", head->data);
        head = head->next;
    }
    printf("\n");
}

int main() {
    struct Node* head1 = NULL;
    struct Node* head2 = NULL;
    struct Node* mergedList = NULL;

    // create first list
    head1 = (struct Node*)malloc(sizeof(struct Node));
    head1->data = 1;
    head1->next = (struct Node*)malloc(sizeof(struct Node));
    head1->next->data = 3;
    head1->next->next = (struct Node*)malloc(sizeof(struct Node));
    head1->next->next->data = 5;
    head1->next->next->next = NULL;

    // create second list
    head2 = (struct Node*)malloc(sizeof(struct Node));
    head2->data = 2;
    head2->next = (struct Node*)malloc(sizeof(struct Node));
    head2->next->data = 4;
    head2->next->next = (struct Node*)malloc(sizeof(struct Node));
    head2->next->next->data = 6;
    head2->next->next->next = NULL;

    printf("List 1: ");
    printList(head1);

    printf("List 2: ");
    printList(head2);

    mergedList = mergeLists(head1, head2);

    printf("Merged list: ");
    printList(mergedList);

    return 0;
}

该程序首先定义了一个结构体`Node`，表示链表的节点。`mergeLists()`函数接受两个有序链表的头结点作为参数，然后遍历这两个链表并将它们合并成一个有序链表。该函数使用双重指针来维护新链表的尾节点，以便可以将新节点添加到新链表的末尾。最后，该函数返回已合并的有序链表的头结点。

`printList()`函数用于打印链表中所有节点的值。在`main()`函数中，创建两个有序链表，然后调用`mergeLists()`函数将它们合并成一个新链表，并打印新链表的所有节点的值。