Earlier quoted context omitted.
Small plug-- this is what I tried to do with https://algodaily.com - going from the easiest algorithms (like "Reverse a String") all the way to Union-Find, while sprinkling implementations of BST, graphs, etc. along the way.
"Reverse a string" is actually one of the hardest interview questions to implement.
Lol. This is so true unless the string is limited to fixed length encodings only, ie ASCII.