在0（1）时间复杂度删除链表节点

代码：

class Solution {
public:
/**
* @param node: a node in the list should be deleted
* @return: nothing
*/
void deleteNode(ListNode *node) {
// write your code here
ListNode *p = node->next;
node->val = p->val;
node->next = p->next;
delete p;

}

};