题解 | #链表分割#

/*
struct ListNode {
    int val;
    struct ListNode *next;
    ListNode(int x) : val(x), next(NULL) {}
};*/
#include <cstddef>
class Partition {
public:
    ListNode* partition(ListNode* pHead, int x) {
        // write code here
        ListNode* Bighead,*Bigtail;
        ListNode* Lesshead,*Lesstail;
        Lesshead = Lesstail = (ListNode*)malloc(sizeof(ListNode));
        Bighead = Bigtail = (ListNode*)malloc(sizeof(ListNode));
        ListNode* pcur = pHead;
        while(pcur)
        {
            if(pcur->val < x)
            {
                Lesstail->next = pcur;
                Lesstail = Lesstail->next;
            }
            else 
            {
                Bigtail->next = pcur;
                Bigtail = Bigtail->next;
            }
            
            pcur = pcur->next;
        }
        Bigtail->next = NULL;
        Lesstail->next = Bighead->next;
        return Lesshead->next;
    }
};