C# Interview Pairing Exercise: Spell Checker/Dictionary

Instructions to explain to the candidate:

Build a dictionary service using C#.

There are three methods to be implemented in the LanguageDictionary class:

• public bool Check(string language, string word)

  Determines if word is in the dictionary for language. If it is, it returns true, if it's not, it will return false.

• public boolean Add(string language, string word)

  Adds word to the dictionary for language. It returns true if it was successfully added. If it was not, it returns false.

• public IEnumerable<string> Search(string word)

  Finds words in all languages that start with the word.

Clarifications:

• The time limit is 1 hour. The first 10 minutes will be spent by the candidate alone, and then the interviewers will join in order to have a pair-programming session.
• The goal is not to complete the three methods, but to complete one or two (if possible), covering all the scenarios, and demonstrating rock-solid coding skills. They should start with the add and check methods.
• TDD is expected and required.
• Everything should be kept simple and in memory. There's no need to store information in external files or a DB.
• New classes can be added to the project, but remember the goal is to keep everything simple.
• Internet can be used to search for information.
• Any questions can be asked to the interviewers.