Leetcode "Linked list": Partition list

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Title Requirements:

Given a linked list and a value x, partition it such that all nodes less than x come before nodes greate R than or equal to x.

You should preserve the original relative order of the nodes in each of the.

For example,
Given 1->4->3->2->5->2 and x = 3,
Return 1->2->2->4->3->5 .

The problem can be greatly facilitated by the use of dummy nodes, the specific procedures are as follows:

1 /**2 * Definition for singly-linked list.3 * struct ListNode {4 * int val;5 * ListNode *next;6 * ListNode (int x): Val (x), Next (NULL) {}7  * };8  */9 classSolution {Ten  Public: Onelistnode* partition (listnode* head,intx) { A         if(!head | |!head->next) -             returnhead; -          theListNode *dummy =NewListNode (int_min); -Dummy->next =head; -ListNode *parnode =dummy; -ListNode *prenode = nullptr, *curnode =nullptr; +          while(Parnode && Parnode->val <x) -         { +Prenode =Parnode; AParnode = parnode->Next; at         } -          -Parnode =Prenode; -         if(!parnode | |!parnode->next) -         { -Head = dummy->Next; in             Deletedummy; -dummy =nullptr; to             returnhead; +         } -          thePrenode = parnode->Next; *Curnode = prenode->Next; $          while(Curnode)Panax Notoginseng         { -             if(Curnode->val <x) the             { +ListNode *nextpar = parnode->next, *nextcur = curnode->Next; AParnode->next =Curnode; theCurnode->next =Nextpar; +Parnode = parnode->Next; -                  $Curnode =nextcur; $Prenode->next =Curnode; -             } -             Else the             { -Prenode = prenode->Next;WuyiCurnode = curnode->Next; the             } -         } Wu          -Head = dummy->Next; About         Deletedummy; $dummy =nullptr; -          -         returnhead; -     } A};

Leetcode "Linked list": Partition list