10 lines
241 B
Text
10 lines
241 B
Text
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defmodule ISO do
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def long_year?(y) do
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{:ok, jan1} = Date.new(y,1,1)
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{:ok, dec31} = Date.new(y,12,31)
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Date.day_of_week(jan1) == 4 or Date.day_of_week(dec31) == 4
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end
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end
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IO.inspect(Enum.filter(1990..2050, &ISO.long_year?/1))
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