//最小要素(root)を削除
public Puzzle Pop()
{
Puzzle ret = root.val;
root = Meld(root.l, root.r);
Count--;
return(ret);
}
private SkewHeapNode CloneShallowSub(SkewHeapNode a)
{
if (a == null)
{
return(null);
}
return(new SkewHeapNode(CloneShallowSub(a.l), CloneShallowSub(a.r), a.val));
}
//浅いクローン (node.val(Puzzle)の実体は複製せず参照値をコピー) (木の各ノードを複製する)
public SkewHeap CloneShallow()
{
SkewHeapNode node = CloneShallowSub(root);
SkewHeap ret = new SkewHeap();
ret.root = node;
ret.Count = Count;
return(ret);
}
//2つのヒープをマージする (ここの実装が本質！）
private SkewHeapNode Meld(SkewHeapNode a, SkewHeapNode b)
{
if (a == null)
{
return(b);
}
if (b == null)
{
return(a);
}
if (a.val.boardScore > b.val.boardScore)
{
Generic.Swap <SkewHeapNode>(ref a, ref b);
}
a.r = Meld(a.r, b);
Generic.Swap <SkewHeapNode>(ref a.l, ref a.r);
return(a);
}
public Puzzle MaxValueSub(SkewHeapNode a)
{
if (a == null)
{
return(null);
}
Puzzle ret = MaxValueSub(a.l);
Puzzle res = MaxValueSub(a.r);
if (res != null && (ret == null || ret.boardScore < res.boardScore))
{
ret = res;
}
if (ret == null || ret.boardScore < a.val.boardScore)
{
ret = a.val;
}
return(ret);
}
public SkewHeapNode(SkewHeapNode l, SkewHeapNode r, Puzzle puzzle)
{
this.l = l;
this.r = r;
this.val = puzzle;
}
public SkewHeapNode(Puzzle puzzle)
{
val = puzzle;
l = null;
r = null;
}
//要素xを追加
public void Push(Puzzle x)
{
root = Meld(root, new SkewHeapNode(x));
Count++;
}
//空のヒープを作る
public SkewHeap()
{
root = null;
Count = 0;
}