[LeetCode]Rotate List

题目

[code]Given 1->2->3->4->5->NULL and k = 2,
return 4->5->1->2->3->NULL.

题解

代码

[code]ListNode* rotateRight(ListNode* head, int k) {
    if(!head || !k || !head->next){
        return head;
    }
    int n = 1;
    ListNode *p = head;
    while(p->next){
        p = p->next;
        n++;
    }
    k %= n;
    n -= k;
    p->next = head;
    if(k){
        while(n--){
            p = p->next;
        }
    }
    head = p->next;
    p->next = NULL;
    return head;
}