ensure_question.rb

# Given a string, write a function that returns the string with a question mark ("?") appends to the end, unless the original string ends with a question mark, in which case, returns the original string.

def ensure_question(s)
    if s.end_with?("?")
        s
    else
        s + "?"
    end
end

#testing
ensure_question("Yes") 
ensure_question("No?")