# 思路

如果當前 node 與下一個 node 相同，將當前 node 接到下下一個 node

# 參考程式碼

	/**
	* Definition for singly-linked list.
	* struct ListNode {
	* int val;
	* ListNode *next;
	* ListNode() : val(0), next(nullptr) {}
	* ListNode(int x) : val(x), next(nullptr) {}
	* ListNode(int x, ListNode *next) : val(x), next(next) {}
	* };
	*/

	static auto fast_io = []
	{
	ios::sync_with_stdio(false);
	cout.tie(nullptr);
	cin.tie(nullptr);
	return 0;
	}();

	class Solution {
	public:
	ListNode* deleteDuplicates(ListNode* head)
	{
	ListNode* cur = head;

	while(cur && cur->next)
	{
	if (cur->val == cur->next->val) cur->next = cur->next->next;
	else cur = cur->next;
	}

	return head;
	}
	};