• 759

What will I learn?


In this puzzle, you learn new ways and reasons to store data in optimized structures such as tries and get a better understanding of graph/tree theory.

External resources



The goal of this puzzle is to store multiple phone numbers in a compact way, using a tree data structure, then count all the nodes there are in this tree. Be careful that you may need several tree roots.

Solve it

A higher resolution is required to access the IDE


Dang, all those telephone numbers are impossible to remember! What if we were to invent a new way to store phone numbers so that they take the least memory space? It is your task today to achieve that hard work. Then call me, maybe ?

Online Participants