private static TreeInfo Traverse(Tree1 node)
{
if (node.L == null && node.R == null)
{
return(new TreeInfo(1, 0));
}
if (node.L == null)
{
var orphan = Traverse(node.R);
return(new TreeInfo(1, Math.Max(orphan.perfectDeeper, orphan.perfectSoFar)));
}
else if (node.R == null)
{
var orphan = Traverse(node.L);
return(new TreeInfo(1, Math.Max(orphan.perfectDeeper, orphan.perfectSoFar)));
}
else
{
var left = Traverse(node.L);
var right = Traverse(node.R);
var deeperBelow = new [] { left.perfectDeeper, right.perfectDeeper, left.perfectSoFar, right.perfectSoFar }.Max();
if (left.perfectSoFar != right.perfectSoFar)
{
// when anything non-perfect, return deeper one
return(new TreeInfo(0, deeperBelow));
}
else
{
// both subtrees have perfect node head
var perfectOnLevel = left.perfectSoFar <= right.perfectSoFar
? new TreeInfo(left.perfectSoFar + 1, deeperBelow)
: new TreeInfo(right.perfectSoFar + 1, deeperBelow);
return(perfectOnLevel);
}
}
}
internal static string WriteTree(Tree1 n)
{
Queue <Tree1> nodes = new Queue <Tree1>();
nodes.Enqueue(n);
var sb = new List <string>();
while (nodes.Any())
{
var node = nodes.Dequeue();
sb.Add(node != null ? node.X.ToString() : "N");
if (node != null)
{
nodes.Enqueue(node.L);
nodes.Enqueue(node.R);
}
}
while (sb.Any() && sb.Last() == "N")
{
sb.RemoveAt(sb.Count - 1);
}
return(string.Join(" ", sb));
}
internal static Tree1 ReadTree(string s)
{
var data = new Queue <int?>(s.Split().Select(s1 => s1 == "N" ? (int?)null : int.Parse(s1, format)));
if (!data.Any())
{
return(null);
}
Tree1 NextNode()
{
var value = data.Dequeue();
if (value == null)
{
return(null);
}
return(new Tree1(value.Value));
}
Queue <Tree1> currentLevel = new Queue <Tree1>();
Queue <Tree1> nextLevel = new Queue <Tree1>();
Tree1 root = NextNode();
if (root == null)
{
return(null);
}
currentLevel.Enqueue(root);
while (data.Any())
{
while (currentLevel.Any() && data.Any())
{
var node = currentLevel.Dequeue() !;
node.L = NextNode();
if (node.L != null)
{
nextLevel.Enqueue(node.L);
}
if (data.Any())
{
node.R = NextNode();
if (node.R != null)
{
nextLevel.Enqueue(node.R);
}
}
}
var tmp = nextLevel;
nextLevel = currentLevel;
currentLevel = tmp;
if (data.Any() && !currentLevel.Any())
{
throw new Exception("wrong node data");
}
}
return(root);
}
internal Tree1(int item)
{
X = item;
L = R = null;
}
private static int FindBiggestSubtree(Tree1 root)
{
var best = Traverse(root);
return((1 << Math.Max(best.perfectSoFar, best.perfectDeeper)) - 1);
}