public void SelectFirstOrDefault90()
{
var root = new QTreeNode <int>(1);
root.Insert(new QTreeNode <int>(2));
root.Child(0).Insert(new QTreeNode <int>(3));
root.Insert(new QTreeNode <int>(4));
root.Insert(new QTreeNode <int>(5));
root.Child(2).Insert(new QTreeNode <int>(6));
root.Child(2).Child(0).Insert(new QTreeNode <int>(7));
Assert.True(root.SelectFirstOrDefault(x => x == 90) == 0, "root.SelectFirstOrDefault(x => x == 90) == 0");
}
public void SelectFirstOrDefaultNotFound()
{
var root = new QTreeNode <int>(1);
root.Insert(new QTreeNode <int>(2));
root.Child(0).Insert(new QTreeNode <int>(3));
root.Insert(new QTreeNode <int>(4));
root.Insert(new QTreeNode <int>(5));
root.Child(2).Insert(new QTreeNode <int>(6));
root.Child(2).Child(0).Insert(new QTreeNode <int>(7));
Assert.True(root.SelectFirstOrDefault(x => x == 123) == default(int),
"root.SelectFirstOrDefault(x => x == 123) == 123");
}