合并两个排序链表 - C++

class Solution {
public:
/**
* @param ListNode l1 is the head of the linked list
* @param ListNode l2 is the head of the linked list
* @return: ListNode head of linked list
*/
ListNode *mergeTwoLists(ListNode *l1, ListNode *l2) {
int a[10000];
ListNode *newnode,*dd;
newnode=new ListNode;
dd=newnode;
int i=1;
while(l1!=NULL)
{
a[i]=l1->val;
i++;
l1=l1->next;
}
while(l2!=NULL)
{
a[i]=l2->val;
i++;
l2=l2->next;
}
for(int x=1;x<i;x++)
for(int y=x;y<i;y++)
{
if(a[x]>a[y])
{
int t=a[x];
a[x]=a[y];
a[y]=t;
}
}
for(int j=1;j<i;j++)
{
ListNode *newNode;
newNode=new ListNode;
newNode->val=a[j];
newnode->next=newNode;
newnode=newNode;
}
if(dd==NULL)
return dd;
else
return dd->next;
// write your code here
}
};