[LeetCode 第6题] -- Insertion Sort List

题目链接: Insertion Sort List
题目意思: 利用插入排序，对链表排序
代码:
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
void sort (vector<ListNode*> &arrList, int size);
ListNode *insertionSortList(ListNode *head);
};

void Solution::sort (vector<ListNode*> &arrList, int size) {
for (int i = 1; i < size; i++) {
int j = i-1;
int tmp = arrList[i]->val;
for (j = i-1; j >= 0; j--) {
if (tmp >= arrList[j]->val) {
break;
}
arrList[j+1]->val = arrList[j]->val;
}
if (j < (i-1)) {
arrList[j+1]->val = tmp;
}
}
}

ListNode* Solution::insertionSortList(ListNode *head) {
if (NULL == head) {
return NULL;
}
int size = 0;
ListNode *tmpHead = head;
while (tmpHead != NULL) {
size++;
tmpHead = tmpHead->next;
}
vector<ListNode*> arrList;
tmpHead = head;
while (tmpHead != NULL) {
arrList.push_back(tmpHead);
tmpHead = tmpHead->next;
}
sort(arrList, size);
return head;
}