/*
struct ListNode {
int val;
struct ListNode *next;
ListNode(int x) :
val(x), next(NULL) {
}
};*/
class Solution {
public:
ListNode* Merge(ListNode* pHead1, ListNode* pHead2)
{
ListNode* head = new ListNode(-1);
ListNode* dummy = head;
for(;pHead1 != NULL || pHead2 != NULL;){
int v1 = pHead1 == NULL ? INT_MAX : pHead1->val;
int v2 = pHead2 == NULL ? INT_MAX : pHead2->val;
if(v1 < v2){
head->next = pHead1;
pHead1 = pHead1 == NULL ? NULL : pHead1->next;
}
else{
head->next = pHead2;
pHead2 = pHead2 == NULL ? NULL : pHead2->next;
}
head = head->next;
}
return dummy->next;
}
};