Balance Factor

AnalysisintermediateAVL Tree

Left height minus right height. Every node must stay within -1, 0 or 1.

Decision · step 6 of 26AVL Tree: Already balanced, no rotations

At 20: left height 1, right height 0, balance 1. Within one, so it stays.

Open in the player →or start at step 6

What you will see

Each node shows its factor; the one outside the range is flagged.

How avl tree works →

Cost

Space	`O(1)`

How you work with it here

play it through, step one change at a time, scrub to any step, run it on your own input, predict what happens next, try operations in any order.

Screen readers: Nodes announce value, left child and right child; each step announces the comparison and the direction taken or the structural change.

Reduced motion: Focus jumps node to node with a static ring; rotations become a crossfade between the two layouts.

Before this

AVL Tree

Leads to

Topics that need this one first.

Left Rotation Right Rotation

Taught by the same lesson

AVL Tree covers these too, in the same run.

AVL Tree AVL Insert with Rebalancing Left Rotation Left-Right and Right-Left Rotations Right Rotation AVL Delete with Rebalancing