Red-Black Example 1 Solution

These screen shots were taken from this website. It's a Java applet and the source code is freely available there.

Original tree: (2, 14, 11, 1, 7, 5, 8, 15)

Insert 4:

Uncle is red, so recolor trinode. X is now 7, Y is now 14. Y is BLACK, X is RIGHT,

so set X to 2 and rotate LEFT about new X (promote 7).

and rotate RIGHT about X's Grandparent (11) (promote 7 again)

and set Parent to Black and Grandparent to RED

Insert 6:

Insert 9:

Insert 10. Parent is RIGHT child, Uncle is BLACK (null), X is RIGHT,

so rotate LEFT about X's Grandparent (8), (promote X's parent, 9)

and set Parent to BLACK and (old) Grandparent to RED: