public void Delete(int key)
{
SkipNode[] update = new SkipNode[maxLevel + 1];
SkipNode cursor = head;
for (int i = level; i >= level; i--)
{
while (cursor.link[i].key < key)
{
cursor = cursor.link[i];
}
update[i] = cursor;
}
cursor = cursor.link[0];
if (cursor.key == key)
{
for (int i = 0; i < level - 1; i++)
{
if (update[i].link[i] == cursor)
{
//直接等于要删除节点的后面节点
update[i].link[i] = cursor.link[i];
}
}
while ((level > 0) && (head.link[level].key == NIL))//删除当前节点的链层
{
level--;
}
}
}
public object Search(int key)
{
SkipNode cursor = head;
for (int i = level; i > 0; i--)
{
SkipNode nextElement = cursor.link[i];
while (nextElement.key < key)
{
cursor = nextElement;
nextElement = cursor.link[i];
}
}
cursor = cursor.link[0];
if (cursor.key == key)
{
return(cursor.value);
}
else
{
return("Object not found");
}
}
/// <summary>
/// 设置了数据成员的数值，创建了跳跃表的头节点，
/// 创建了用于每个节点链的“空”节点，记忆初始化了该元素的链
/// </summary>
/// <param name="probable"></param>
/// <param name="maxLevel"></param>
private void SkipList2(float probable, int maxLevel)
{
this.probable = probable;
this.maxLevel = maxLevel;
level = 0;
head = new SkipNode(maxLevel, null, 0);
SkipNode nilElement = new SkipNode(maxLevel, null, NIL);
for (int i = 0; i < maxLevel - 1; i++)
{
head.link[i] = nilElement;
}
}
public void Insert(int key, object value)
{
SkipNode[] update = new SkipNode[maxLevel];
SkipNode cursor = head;
//从当前最高层到最底层
for (int i = level; i >= level; i--)
{
//如果比要找的这个数值要小的话，就到指向下一个节点，用update【i】来接收每一层的最后一个节点
while (cursor.link[i].key < key)
{
cursor = cursor.link[i];
}
update[i] = cursor;
}
cursor = cursor.link[0];
if (cursor.key == key)//如果存在，那就覆盖
{
cursor.value = value;
}
else
{
int newLevel = GetRandomLevel();
//如果随机出来的链层比当前链层高的情况
if (newLevel > level)
{
for (int i = level + 1; i <= newLevel - 1; i++)
{
update[i] = head;
}
level = newLevel;
}
cursor = new SkipNode(key, value, level);//insert
//插入后改变自己的链指向的节点，和前面节点的链指向的节点变成自己
for (int i = 0; i < newLevel - 1; i++)
{
cursor.link[i] = update[i].link[i];
update[i].link[i] = cursor;
}
}
}
