## Delete Node in a Linked List

Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.
Supposed the linked list is 1 -> 2 -> 3 -> 4 and you are given the third node with value 3, the linked list should become 1 -> 2 -> 4 after calling your function.

### Analysis:

To solve this problem, the key point is "overwrite" !

Usually we are thinking "skip" the node we want to delete by:
1 -> 2 -> 3 -> 4 -> Null, delete 3, we have:
1 -> 2--------> 4 -> Null.

However in this problem, the previous node is unknown.
So, what we should do is to overwrite the node  "3" by node "4":
1 -> 2 -> 3 -> 4->Null, delete 3, we have:
1 -> 2 -> 4->Null.

Just pay attention to the case that the node is the last node.

### Code(C++):

/**
* struct ListNode {
*     int val;
*     ListNode *next;
*     ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
void deleteNode(ListNode* node) {
if (node->next){
node->val = node->next->val;
node->next = node->next->next;
}else{
node = NULL;
}
}
};


### Code(Python):

# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
def deleteNode(self, node):
"""
:type node: ListNode
:rtype: void Do not return anything, modify node in-place instead.
"""
if node.next:
node.val = node.next.val
node.next = node.next.next
else:
node = None