C++ 代码

class Solution {
public:
    ListNode* deleteDuplication(ListNode* head) {
        if (head == nullptr || head->next == nullptr)return head;

        ListNode* temp = head->next;

        while (temp && temp->val == head->val)temp = temp->next;//此时temp->val != head->val;

        if (temp == head->next)
            head->next = deleteDuplication(head->next);
        else
            head = deleteDuplication(temp);
        return head;
    }
};