题解 | #链表分割#

class Partition {
public:
    ListNode* partition(ListNode* pHead, int x) {
        // write code here
        ListNode* bigTail = NULL;  
        ListNode* bigHead = NULL;  //大

         ListNode* littleTail = NULL;  //小
         ListNode* littleHead = NULL;    

        littleTail = littleHead = (ListNode*)malloc(sizeof(ListNode));
        littleTail->next = NULL;

        bigTail = bigHead = (ListNode*)malloc(sizeof(ListNode));
        bigTail->next = NULL;

        ListNode* cur = pHead;
        while(cur)
        {
            if(cur->val < x)
            {
                littleTail->next = cur;
                littleTail = littleTail->next;
            }
            else
            {
                bigTail->next = cur;
                bigTail = bigTail->next;
            }

            cur = cur->next;
        }

        littleTail->next = bigHead->next;

        bigTail->next = NULL;//

        pHead = littleHead->next;

        free(bigHead);
        free(littleHead);


        return pHead;
    }
};