class Auto
	attr_reader :position
	attr_writer :position
	def initialize(position,v0)
		@position=position
		@v0=v0
	end
	def update_position
		@position=@position+@v0
	end
end
 
class Simulation
	def initialize(s,t,vm,ai,ad)
		@s=s
		@t=t
		@vm=vm
		@ai=ai
		@ad=ad
	end
 
	def simulate(autos)
	autos.sort_by { |x| x.position} 
	#autos.each {|a| p a}	
		for i in 1..@t
			autos.each{|a| a.update_position+@ai}
			autos.each {|a,b| p	a.position-b.position}#здесь ошибка undefined method `position' for nil:NilClass
 
=begin
			case dist
			when dist<=10
				autos[i-1].position-$ad
			when dist=0
						autos.delete(i-1)
			end
=end
 
	end
	end
end
 
auto_data=[[0,2],[5,10],[7,20]]
autos=[]
auto_data.each do |a|
autos.push(Auto.new(a[0],a[1]))
end	
s=Simulation.new(100,10,30,5,-2)
 
s.simulate(autos)#запускаем симуляцию
# your code goes here

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