20 lines
505 B
Ruby
20 lines
505 B
Ruby
def mdroot(n)
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mdr, persist = n, 0
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until mdr < 10 do
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mdr = mdr.to_s.each_char.map(&:to_i).inject(:*)
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persist += 1
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end
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[mdr, persist]
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end
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puts "Number: MDR MP", "====== === =="
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[123321, 7739, 893, 899998].each{|n| puts "%6d: %d %2d" % [n, *mdroot(n)]}
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counter = Hash.new{|h,k| h[k]=[]}
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0.step do |i|
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counter[mdroot(i).first] << i
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break if counter.values.all?{|v| v.size >= 5 }
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end
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puts "", "MDR: [n0..n4]", "=== ========"
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10.times{|i| puts "%3d: %p" % [i, counter[i].first(5)]}
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