gistfile1.builder

def solve(input, name_index, left_index, right_index)
  min, result = 100, nil

  input.each_line do |line|
    next unless line =~ /^\s*\d/
    row = line.strip.split(/\s+/).map { |e| (digits = e[/\d+/]) ? digits.to_i : e }

    name  = row[name_index]
    left  = row[left_index]
    right = row[right_index]
    diff  = (left - right).abs

    min, result = diff, name if diff < min
  end

  result
end

p solve(File.read("part1/weather.dat"), 0, 1, 2)  # => 14
p solve(File.read("part2/football.dat"), 1, 6, 8) # => "Aston_Villa"