public void Test_1()
{
var iterator = new BstIterator(new TreeNode(1));
Assert.True(iterator.HasNext());
Assert.Equal(1, iterator.Next());
Assert.False(iterator.HasNext());
}
public void Test_5()
{
var node2 = new TreeNode(2);
var node3 = new TreeNode(3);
var node1 = new TreeNode(1);
node3.left = node1;
node1.right = node2;
var iterator = new BstIterator(node3);
Assert.True(iterator.HasNext());
Assert.Equal(1, iterator.Next());
Assert.True(iterator.HasNext());
Assert.Equal(2, iterator.Next());
Assert.True(iterator.HasNext());
Assert.Equal(3, iterator.Next());
Assert.False(iterator.HasNext());
}
