> 
=begin

Here is my solution.
It accepts input like this:
2500_5000  #lower_upper
2500_      #lower only
_5000      #upper only

=end

min,max = ARGV[0].split(/_/)
a,b,c = (1000..3000).to_a,(6000..10000).to_a,(500..2500).to_a
l,u = min.to_i,max.to_i
u = [a,b,c].flatten.max if max == nil
l = 0 if min == ""
cust = (l..u).to_a
p "a" unless (cust & a).empty?
p "b" unless (cust & b).empty?
p "c" unless (cust & c).empty?

Harry

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