My solutions and proposals for strings

[mtonina]

Hi @conanbatt

First case: I implemented three approaches (I'm learning Typescript so I took the opportunity to experiment). I used a different approach for non-additional-datastructure requirement. Instead of running linear, I sort the string so I can fix it with O(nlog(n)) complexity. I provide other two solutions (one with extra data structure and TS, and other with pure JS). I'm an old Java guy, so I'm trying to move to javascript and force myself to learn it to improve my skills.

Second scenario: I made it with a different approach, I guess it can be a little more complicated (I use a Set and a hash instead of two hashes) but I avoid traversing all the second hash again to check that it's 0 in all keys. In addition, I added a new test case to check if someone forgot to validate set/hashmap at the end. It can lead to false positives without this check.

I added a different approach for solving exercise 3 -with an array and replacing it in place, trying to use the original idea of mutable structure-. I hope it help to expand the combination of solutions.

All the other exercises are done with my approach trying to achieve the minimum time complexity.