3 research outputs found
A symbolic-arithmetic for teaching double-black node removal in red-black trees
A red-black (RB) tree is a data structure with red and black nodes
coloration. The red and black color of nodes make up the principal component
for balancing a RB tree. A balanced tree has an equal number of black nodes on
any simple path. But when a black leaf node is deleted, a double-black (DB)
node is formed, thus, causing a reduction in black heights and the tree becomes
unbalanced. Rebalancing a RB tree with a DB node is a fairly complex process.
Teaching and learning the removal of DB nodes is also challenging. This paper
introduces a simplified novel method which is a symbolic-algebraic arithmetic
procedure for the removal of DB nodes and the rebalancing of black heights in
RB trees. This simplified approach has enhanced student learning of the DB node
removal in RB trees. Feedback from students showed the learnability,
workability and acceptance of the symbolic-algebraic method in balancing RB
trees after a delete operation.Comment: 18 page