gistfile1.txt

channel= Channel(Int32).new
spawn do
        p "Start1: #{Time.now}"
        i= 0
        100_000_000.times do
                channel.send i=-1
                channel.receive
        end
        p "End1: #{Time.now}"
end

spawn do
        p "Start2: #{Time.now}"
        i= 0
        100_000_000.times do
                channel.receive
                channel.send i+= 1
        end
        p "End2: #{Time.now}"
end

Fiber.yield