1 Insertion sort iterates, consuming one input element each repetition, and growing a sorted output list.
2 At each iteration, insertion sort removes one element from the input data, finds the location it belongs within the sorted list, and inserts it there.
3 It repeats until no input elements remain.

Input: 4->2->1->3
Output: 1->2->3->4

Input: -1->5->3->4->0
Output: -1->0->3->4->5

 1 ListNode* insertionSortList(ListNode* head) {
 2         ListNode* dummy=new ListNode(-1),*cur=dummy;
 3         while(head){
 4             ListNode* t=head->next;
 5             cur=dummy;
 6             while(cur->next&&cur->next->val<=head->val)
 7                 cur=cur->next;
 8             head->next=cur->next;
 9             cur->next=head;
10             head=t;
11         }
12         return dummy->next;
13     }

 1  public ListNode insertionSortList(ListNode head) {
 2         ListNode dummy=new ListNode(-1),cur=dummy;
 3         while(head!=null){
 4             ListNode t=head.next;
 5             cur=dummy;
 6             while(cur.next!=null&&cur.next.val<=head.val)
 7                 cur=cur.next;
 8             head.next=cur.next;
 9             cur.next=head;
10             head=t;
11         }
12         return dummy.next;
13     }

 1  ListNode* insertionSortList(ListNode* head) {
 2         vector<int> m;
 3         while(head){
 4             m.push_back(head->val);
 5             head=head->next;
 6         }
 7         sort(m.begin(),m.end());
 8         ListNode* newhead=new ListNode(-1);
 9         while(!m.empty()){
10             ListNode* cur=new ListNode(m.back());
11             m.pop_back();
12             cur->next=newhead->next;
13             newhead->next=cur;
14         }
15         return newhead->next;
16     }