public void Test()
{
PTree <int> tree = new PTree <int>(1, 10);
var parent2 = tree.AddNode(2, tree.Root);
var parent3 = tree.AddNode(3, tree.Root);
tree.AddNode(4, parent2);
tree.AddNode(5, parent2);
tree.AddNode(6, parent3);
tree.AddNode(7, parent3);
tree.AddNode(8, parent3);
_testOutputHelper.WriteLine($"树的节点数量：{tree.Count}");
_testOutputHelper.WriteLine($"树的根节点：{tree.Root.Data}");
_testOutputHelper.WriteLine("");
_testOutputHelper.WriteLine("树的全部节点：");
foreach (var node in tree.GetChilds())
{
_testOutputHelper.WriteLine($"节点数据：{node.Data}，父节点index：{node.ParentIndex}");
}
_testOutputHelper.WriteLine("");
_testOutputHelper.WriteLine($"节点数据为“{parent2.Data}”的子节点为：");
foreach (var node in tree.GetChilds(parent2))
{
_testOutputHelper.WriteLine($"节点数据：{node.Data}，父节点index：{node.ParentIndex}");
}
_testOutputHelper.WriteLine("");
_testOutputHelper.WriteLine($"节点数据为“{parent3.Data}”的子节点为：");
foreach (var node in tree.GetChilds(parent3))
{
_testOutputHelper.WriteLine($"节点数据：{node.Data}，父节点index：{node.ParentIndex}");
}
}