tuple.rb

# * question 2. nt (num tuple)

# Here is the definition of the number tuple. Please write a function to decide whether a string is a valid num tuple representation.

# item -> () or [0-9]+ or nt
# nt -> (item,item,item+)

# f(“()”) -> true
# f(“(1,2,988)”) -> true
# f(“(1,23,(4,5),076)”) -> true

class TupleValidation
  def self.is_tuple?(string)
    return !!(string =~ /\([0-9\,]*|[\(\)]?[0-9\,]*\)/) &&
      string.count("(") == string.count(")")
  end
end