I ran across this looking for ways to build the Trie. I suspect in the past couple of years the answer as come, but I figured I would post and answer if anyone else comes across the same thing.

The use of the bool value “IsEnd” is unfortunate as it would lead to a misconception. It would be better to use “IsWord”, or “EndsWord”. The value is there to indicate the transversed keys constitute a word, NOT the end of the nodes in the trie. In your example the keys might look more like this.

Think words (Read, Reader, Reading);

Root->R->E->A->D(EndsWord = True)->E->R(EndsWord = true)->S(EndsWord=true)
->I->N->G(EndsWord=true)

Root->R->E->A->D(IsEnd = True)
Root->R->A->D->E->R(IsEnd = true)

Is this not duplication ? Also as we have only 26 nodes under each node, there is no scope for duplication also and we cannot have the below scenario:
Root->R->E->A->D(isEnd = True)->E->R(IsEnd = True)

Then how will the 2 words “Read” and “Reader” will ge stored in the tree ?