Hard Strings Cheat Sheet

A sequence of characters, either as a literal constant or as some kind of variable, that can have its elements be mutated and length changed.

Interview Problems

Why do I see duplicate challenges? You'll see duplicates because a question may fall into different categories. We keep them here because we believe that it is good to sporadically review old problems. They are optional if already completed-- but reviewing them (and more importantly re-doing them with the new knowledge) will ensure that you've internalized the patterns.