Insertion Sort List 使用插入排序将链表排序

/**

* Definition for singly-linked list.

* struct ListNode {

* int val;

* ListNode *next;

* ListNode(int x) : val(x), next(NULL) {}

* };

*/

class Solution {

public:// 13 79 6 10

ListNode *insertionSortList(ListNode *head) {

if(head==NULL) return head;

ListNode dummy(-1);

dummy.next=head;

ListNode *prev=head;

ListNode *cur=prev->next;

while(cur)

{

if(prev->val<=cur->val)

{

prev=cur;

cur=cur->next;

}

else

{

ListNode *insertprev=&dummy;

ListNode *insertcur=dummy.next;

while(insertcur->val<cur->val)

{

insertprev=insertcur;

insertcur=insertcur->next;

}

prev->next=cur->next;

cur->next=insertcur;

insertprev->next=cur;

cur=prev->next;

}

}

return dummy.next;

}

};