take_natural_numbers.rb

# http://v2ex.com/t/74002
list = [0, 0, 0,
        2295, 2295, 1530,
        0, 0, 0, 0, 0,
        1020, 1530, 1530, 1530, 1530, 2295, 2550, 1785,
        0, 0, 0, 0, 0,
        1020, 1530, 1530, 1530, 1530, 2295, 2550,
        0, 0, 0, 0, 0,
        1275, 1530, 1530, 1530, 1530, 1530,
        0, 0, 0, 0, 0, 0]

index = 0
natural_number_list = []

detect_natural = proc { list.detect { |i| i != 0 } }

while detect_natural.call
  index += list.index(detect_natural.call)
  list = list[list.index(detect_natural.call)..list.length]
  natural_numbers = list.take_while { |i| i != 0 }
  natural_number_list.push([natural_numbers.length,
                            [index, index + natural_numbers.length - 1]])
  index += natural_numbers.length
  list.shift(natural_numbers.length)
end

p natural_number_list
# => [[3, [3, 5]], [8, [11, 18]], [7, [24, 30]], [6, [36, 41]]]