public NodeVector(Btree <T> tree, T key, bool leftEdge) : this(tree)
{
for (Node node = tree.root;;)
{
int hi = node.KeyCount;
if (leftEdge)
{
for (int lo = 0; lo != hi;)
{
int mid = (lo + hi) >> 1;
int diff = tree.keyComparer.Compare(key, node.GetKey(mid));
if (diff <= 0)
{
if (diff == 0)
{
this.IsFound = true;
}
hi = mid;
}
else
{
lo = mid + 1;
}
}
}
else
{
for (int lo = 0; lo != hi;)
{
int mid = (lo + hi) >> 1;
int diff = tree.keyComparer.Compare(key, node.GetKey(mid));
if (diff < 0)
{
hi = mid;
}
else
{
if (diff == 0)
{
this.IsFound = true;
}
lo = mid + 1;
}
}
}
this.indexStack.Add(hi);
this.nodeStack.Add(node);
if (node is Branch branch)
{
node = branch.GetChild(hi);
}
else
{
return;
}
}
}
/// <summary>Make a path to leftmost branch or leaf at the supplied level.</summary>
/// <param name="tree">Target of path.</param>
/// <param name="level">Level of node to seek (root is level 0).</param>
/// <remarks>Used only for diagnostics.</remarks>
public NodeVector(Btree <T> tree, int level) : this(tree)
{
this.IsFound = false;
Push(tree.root, 0);
for (Node node = TopNode; level > 0; --level)
{
node = ((Branch)node).GetChild(0);
Push(node, 0);
}
}
public BaseEnumerator(Btree <T> owner, int count)
{
this.tree = owner;
this.stageFreeze = owner.stage;
this.state = -1;
if (count > 0)
{
this.start = count;
}
if (this.start <= owner.leftmostLeaf.KeyCount)
{
this.leaf = owner.leftmostLeaf;
this.leafIndex = this.start;
}
}
public BaseEnumerator(Btree <T> owner, bool isReverse = false)
{
this.tree = owner;
this.isReverse = isReverse;
this.stageFreeze = tree.stage;
this.state = -1;
if (isReverse)
{
this.start = owner.root.Weight - 1;
this.leaf = owner.rightmostLeaf;
this.leafIndex = owner.rightmostLeaf.KeyCount - 1;
}
else
{
this.leaf = owner.leftmostLeaf;
}
}
/// <summary>Perform search and store the result.</summary>
/// <param name="tree">Tree to search.</param>
/// <param name="key">Value to find.</param>
public NodeVector(Btree <T> tree, T key) : this(tree)
{
for (Node node = tree.root;;)
{
this.nodeStack.Add(node);
int ix = tree.keyComparer == Comparer <T> .Default?node.Search(key)
: node.Search(key, tree.keyComparer);
if (node is Branch branch)
{
ix = (ix < 0) ? ~ix : ix + 1;
this.indexStack.Add(ix);
node = branch.GetChild(ix);
}
else
{
this.IsFound = ix >= 0;
this.indexStack.Add(this.IsFound ? ix : ~ix);
return;
}
}
}
public PairEnumerator(Btree <T> owner, Func <KeyValuePair <T, V>, bool> condition) : this(owner)
public PairEnumerator(Btree <T> owner, int count) : base(owner, count)
{
}
public PairEnumerator(Btree <T> owner, bool isReverse = false, bool nonGeneric = false) : base(owner, isReverse)
=> this.NonGeneric = nonGeneric;
public ValueEnumerator(Btree <T> owner, Func <V, int, bool> condition) : base(owner)
=> Bypass3(condition, (leaf, ix) => ((PairLeaf <V>)leaf).GetValue(ix));
public ValueEnumerator(Btree <T> owner, int count) : base(owner, count)
{
}
public ValueEnumerator(Btree <T> owner, bool isReverse = false) : base(owner, isReverse)
{
}
public KeyEnumerator (Btree<T> owner, Func<T,int,bool> condition) : base (owner) => Bypass3 (condition, (leaf,ix) => leaf.GetKey (ix));
/// <summary>Make an empty path.</summary>
/// <param name="tree">Target of path.</param>
public NodeVector(Btree <T> tree)
{
this.tree = tree;
this.indexStack = new List <int>();
this.nodeStack = new List <Node>();
}
public static NodeVector CreateFromIndex(Btree <T> tree, int index)
{
Debug.Assert(index <= tree.root.Weight);
var path = new NodeVector(tree);
if (index == 0)
{
for (Node n0 = tree.root;;)
{
path.indexStack.Add(0);
path.nodeStack.Add(n0);
if (n0 is Branch bh)
{
n0 = bh.GetChild(0);
}
else
{
return(path);
}
}
}
else if (index >= tree.root.Weight)
{
for (Node n0 = tree.root;;)
{
path.indexStack.Add(n0.KeyCount);
path.nodeStack.Add(n0);
if (n0 is Branch bh)
{
n0 = bh.GetChild(bh.KeyCount);
}
else
{
return(path);
}
}
}
Node node = tree.root;
while (node is Branch branch)
{
for (int ix = 0; ; ++ix)
{
Debug.Assert(ix <= node.KeyCount);
Node child = branch.GetChild(ix);
int cw = child.Weight;
if (cw > index)
{
path.indexStack.Add(ix);
path.nodeStack.Add(node);
node = child;
break;
}
index -= cw;
}
}
path.indexStack.Add(index);
path.nodeStack.Add(node);
return(path);
}
