1.题目要求:

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     struct ListNode *next;
 * };
 */
int compare(const void* a,const void* b)
{
    return (*(int*)a - *(int*)b);
}
struct ListNode* trainningPlan(struct ListNode* l1, struct ListNode* l2) {
    if(l1 == NULL&&l2 == NULL)
        return NULL;
    if(l1 == NULL)
        return l2;
    if(l2 == NULL)
        return l1;
    struct ListNode* cur = l1;
    struct ListNode* cur1 = l2;
    int count = 0;
    while(cur)
    {
        count++;
        cur = cur->next;
    }
    while(cur1)
    {
        count++;
        cur1 = cur1->next;
    }
    //创建数组
    int* number = (int*)malloc(sizeof(int) * count);
    int f = 0;
    cur = l1;
    cur1 = l2;
    //往数组里存值
    while(cur)
    {
        number[f] = cur->val;
        f++;
        cur = cur->next;
    }
    while(cur1)
    {
        number[f] = cur1->val;
        f++;
        cur1 = cur1->next;
    }
    //给数组排序
    qsort(number,count,sizeof(int),compare);
    cur = l1;
    cur1 = l2;
    //连接两个链表
    while(cur->next != NULL)
    {
        cur = cur->next;
    }
    f = 0;
    cur->next = l2;
    cur = l1;
    //把数组的值存入链表中
    while(cur)
    {
        cur->val = number[f];
        f++;
        cur = cur->next;
    }
    return l1;
}