在一个排序的链表中,存在重复的结点,请删除该链表中重复的结点,重复的结点不保留,返回链表头指针。 例如,链表1->2->3->3->4->4->5 处理后为 1->2->5
/*
struct ListNode {
int val;
struct ListNode *next;
ListNode(int x) :
val(x), next(NULL) {
}
};
*/
class Solution {
public:
ListNode* deleteDuplication(ListNode* pHead)
{
ListNode* p = new ListNode(0);
ListNode* q = pHead;
if(q != NULL){
p -> next = q;
}else{
return NULL;
}
ListNode* r = NULL;
while( q != NULL && (r = q -> next) != NULL){
if(q -> val != r -> val){
p = q;
q = r;
}else{
while(r != NULL && q -> val == r -> val){
r = r -> next;
}
if(p -> next == pHead){
pHead = r;
}
p -> next = r;
q = r;
}
}
return pHead;
}
};