Both problems dealt with strings so I would recommend reviewing things such as how to edit a string to be uppercase, lowercase, capitalized, how to parse through a string using delimiters such as whitespace. Question 1 was more dependent on memory and question 2 was more critical thinking/problem-solving. You can use your language of choice so pick wisely. They weren't that difficult but I'd definitely recommend you brush up on strings, but this might change given that previous interviews dealt with arrays. Also, syntax for sure, as you will actually be coding in your language of choice. The point is, you won't have to deal with complex data structures most likely, just hammer down the basics.