2-3 Deletion (Case #1)

Deletion Algorithm:

Deletion in 2-3 Trees is implemented based on the same scenarios we discussed in the last lesson but in the reverse order. The deletion algorithm also takes $O(Logn)$ time. And, just like insertion, deletion also begins from the leaf node. The deletion in 2-3 Trees is performed based on these scenarios:

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Case 1: Element at Leaf:

When the element which needs to be removed is present at the leaf node, we check how many keys are present in that node; this further divides the algorithm into two scenarios:

1.1 Leaf node has more than one key:

If the leaf at which the element to be deleted has more than one key, then simply delete the element.

Example: See the following example where the node has more than one key.