/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
public class Solution {
public ListNode insertionSortList(ListNode head) {
if (head == null || head.next == null) {
return head;
}
ListNode dummy = new ListNode(0);
ListNode prev = dummy;
while (head != null) {
ListNode tmp = head.next;
if (prev.val >= head.val) {
prev = dummy;
}
while (prev.next != null && prev.next.val < head.val) {
prev = prev.next;
}
head.next = prev.next;
prev.next = head;
head = tmp;
}
return dummy.next;
}
}