LeetCode 86 Partition List

LeetCode 86 Partition List

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

You shoshould preserve the original relative order of the nodes in each of the two partitions.

For example,
Given1->4->3->2->5->2And x = 3,
Return1->2->2->4->3->5.

 

The question requires segmentation of the linked list. All elements smaller than X are placed before the elements greater than or equal to X.

The Code is as follows:

 

class Solution {public:    ListNode* partition(ListNode* head, int x) {        if (head == NULL)return head;ListNode tmpHead(0);tmpHead.next = head;ListNode *p = &tmpHead;ListNode *q = p->next;while(q && q->val
 
  next;q = p->next;}while (q != NULL){ListNode * tmpNode = q->next;if(tmpNode == NULL)    break;if (tmpNode->val < x){q->next = tmpNode->next;tmpNode->next = p->next;p->next = tmpNode;p = p->next;}else{    q = q->next;}}return tmpHead.next;    }};