Assertion: tree's root | /r/HasProperty | black
Facets:
Source sentences:
text: The root is black.
text: Property 2 (the root is black) is checked and corrected with case 1.
text: In this case, it is repainted black to satisfy property 2 (the root is black).
text: However, the grandparent G may now violate Property 2 (the root is black) if it is the root or Property 4 (Both children of every red node are black) if it has a red parent.
text: We removed one black node from every path, and the new root is black, so the properties are preserved.