203 remove linked list elements

203. 移除链表元素

cpp：

/**

 * 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) {}

 * };
 */
class Solution {
public:
    ListNode* removeElements(ListNode* head, int val)
    {
        ListNode *dummyHead = new ListNode();
        dummyHead->next = head;

        ListNode *current = dummyHead;
        
        while (current->next != nullptr)
        {
            if (current->next->val == val)
            {
                current->next = current->next->next;
            }
            else
            {
                current = current->next;
            }
        }

        return dummyHead->next;
    }
};

go：

/**

 * Definition for singly-linked list.

 * type ListNode struct {

 *     Val int

 *     Next *ListNode

 * }
 */
func removeElements(head *ListNode, val int) *ListNode {
    dummyHead := &ListNode{Next: head}

    current := dummyHead

    for current.Next != nil {
        if current.Next.Val == val {
            current.Next = current.Next.Next
        } else {
            current = current.Next
        }
    }

    return dummyHead.Next
}