在遍历链表时，可以使用两个指针分别指向前一个节点和当前节点，然后依次比较相邻两个节点的值，如果值相同，则删除当前节点，否则将前一个节点指向当前节点。

示例代码如下：

class Node:
    def __init__(self, val):
        self.val = val
        self.next = None

def deleteDuplicates(head: Node) -> Node:
    
    if not head:
        return head
    
    dummy = Node(0)
    dummy.next = head
    prev = dummy
    cur = head
    
    while cur:
        # 判断当前节点与下一个节点的值是否相等
        if cur.next and cur.val == cur.next.val:
            # 找到下一个不相同的节点
            while cur.next and cur.val == cur.next.val:
                cur = cur.next
            # 删除重复节点
            prev.next = cur.next
        else:
            prev = prev.next
        cur = cur.next
        
    return dummy.next

使用示例：

head = Node(1)
node1 = Node(2)
node2 = Node(2)
node3 = Node(3)
node4 = Node(4)
node5 = Node(4)
node6 = Node(5)

head.next = node1
node1.next = node2
node2.next = node3
node3.next = node4
node4.next = node5
node5.next = node6

print(deleteDuplicates(head).val)   # 输出 1