bool IDictionary.Contains(object jKey)
{
var path = new TreePath <TKey, TValue>(this, (TKey)jKey);
return(path.IsFound);
}
// Leaf has been split so insert the new anchor into a branch.
private void Promote(TreePath <TKey, TValue> path, TKey key, Node <TKey> newNode)
{
for (;;)
{
if (path.Height == 1)
{
Debug.Assert(root == path.TopNode);
// Graft new root.
root = new Branch <TKey>(path.TopNode, Order);
root.Add(key, newNode);
++height;
break;
}
path.Pop();
Branch <TKey> branch = (Branch <TKey>)path.TopNode;
int branchIndex = path.TopNodeIndex;
if (branch.NotFull)
{
// Typical case where branch has room.
branch.InsertKey(branchIndex, key);
branch.Insert(branchIndex + 1, newNode);
break;
}
// Right split an overflowing branch.
Branch <TKey> newBranch = new Branch <TKey>(branch);
int halfway = (branch.KeyCount + 1) / 2;
if (branchIndex < halfway)
{
// Split with left-side insert.
for (int i = halfway;; ++i)
{
if (i >= branch.KeyCount)
{
newBranch.Add(branch.GetChild(i));
break;
}
newBranch.Add(branch.GetKey(i), branch.GetChild(i));
}
TKey newPromotion = branch.GetKey(halfway - 1);
branch.Truncate(halfway - 1);
branch.InsertKey(branchIndex, key);
branch.Insert(branchIndex + 1, newNode);
key = newPromotion;
}
else
{
// Split branch with right-side insert (or cascade promote).
int moveIndex = halfway;
if (branchIndex > halfway)
{
for (;;)
{
++moveIndex;
newBranch.Add(branch.GetChild(moveIndex));
if (moveIndex >= branchIndex)
{
break;
}
newBranch.AddKey(branch.GetKey(moveIndex));
}
newBranch.AddKey(key);
key = branch.GetKey(halfway);
}
newBranch.Add(newNode);
while (moveIndex < branch.KeyCount)
{
newBranch.AddKey(branch.GetKey(moveIndex));
++moveIndex;
newBranch.Add(branch.GetChild(moveIndex));
}
branch.Truncate(halfway);
}
newNode = newBranch;
}
}