#prepare the input which is a string containing new lines
def parse(input)
  data = []
  input.each_line do |line|
    data << line.gsub(/[a-zA-Z]/,"").chomp
  end
  data
end

# result should a single string or integer
def calculate(data)
  result = 0
  data.each do |d|
    d = d.chars.to_a
    num = "#{d.first}"+"#{d.last}"
    result += num.to_i
  end
  result
end