328. 奇偶链表 比较满意 刷题出成效了

 struct ListNode* oddEvenList(struct ListNode* head) {
    if(head==NULL || head->next==NULL) return head;
    struct ListNode *odd = head;
    struct ListNode *even = head->next,*even_head = even;
    struct ListNode *p = NULL;
    while(odd->next&&even->next){
        p = odd->next->next; //记录下一个奇数点
        even->next = p->next; //先让偶数点连接下一个偶数点
        odd->next = p; //奇数点连接下一个奇数点
        odd = p; //奇数点后移
        even = p->next; //偶数点后移
    }
    odd->next = even_head;
    return head;
}