public void Delete(int key)
{
SkipNode <T>[] update = new SkipNode <T> [maxLevel + 1];
SkipNode <T> cursor = header;
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.CompareTo(key) == 0)
{
for (int i = 0; i < level - 1; i++)
{
if (update[i].link[i].CompareTo(cursor) == 0)
{
update[i].link[i] = cursor.link[i];
}
}
while ((level > 0) && (header.link[level].key == NIL))
{
level--;
}
}
}
private SkipList(float probable, int maxLevel)
{
this.probability = probable;
this.maxLevel = maxLevel;
level = 0;
header = new SkipNode <T>(maxLevel, 0, default(T));
SkipNode <T> nilElement = new SkipNode <T>(maxLevel, NIL, default(T));
for (int i = 0; i <= maxLevel - 1; i++)
{
header.link[i] = nilElement;
}
}
public void Insert(int key, T value)
{
var update = new SkipNode <T> [maxLevel];
var cursor = header;
for (int i = level; i >= level; i--)
{
while (cursor.link[i].key.CompareTo(key) < 0)
{
cursor = cursor.link[i];
}
update[i] = cursor;
}
cursor = cursor.link[0];
if (cursor.key.CompareTo(key) == 0)
{
cursor.value = value;
}
else
{
int newLevel = GenRandomLevel();
if (newLevel > level)
{
for (int i = level + 1; i <= newLevel - 1; i++)
{
update[i] = header;
}
level = newLevel;
}
cursor = new SkipNode <T>(newLevel, key, value);
for (int i = 0; i <= newLevel - 1; i++)
{
cursor.link[i] = update[i].link[i];
update[i].link[i] = cursor;
}
}
}
/// <summary>
/// Compares the current object with another object of the same type.
/// </summary>
/// <returns>
/// A value that indicates the relative order of the objects being compared. The return value has the following meanings: Value Meaning Less than zero This object is less than the <paramref name="other"/> parameter.Zero This object is equal to <paramref name="other"/>. Greater than zero This object is greater than <paramref name="other"/>.
/// </returns>
/// <param name="other">An object to compare with this object.</param>
public int CompareTo(SkipNode <T> other)
{
return(value.CompareTo(other.value));
}