From: Harry Kakueki <list.push@...>
Date: 2013-06-01T19:18:22+09:00
Subject: Re: Eloquent Ruby Kaprekar's Number

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Your requirements seem to be different than the definition that I read. See
Josh's solution and link.
For example, you are missing 4879.

Anyway, FWIW.


def try1(n)
  s,a = n.to_s.size,[]
  (s...s*2).each{|y| a << (n **2)/(10**y)+(n**2)%(10**y)}
  a.include?(n)
end

arr = []
(1..100_000).each{|x|arr << x if try1(x)}
p arr #> [1, 9, 45, 55, 99, 297, 703, 999, 2223, 2728, 4879, 4950, 5050,
5292, 7272, 7777, 9999, 17344, 22222, 38962, 77778, 82656, 95121, 99999]



Harry

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<div dir=3D"ltr"><div><div><div>Your requirements seem to be different than=
 the definition that I read. See Josh&#39;s solution and link.<br></div>For=
 example, you are missing 4879.<br><br></div>Anyway, FWIW.<br><br><br>def t=
ry1(n)<br>
=A0 s,a =3D n.to_s.size,[]<br>=A0 (s...s*2).each{|y| a &lt;&lt; (n **2)/(10=
**y)+(n**2)%(10**y)}<br>=A0 a.include?(n)<br>end<br><br>arr =3D []<br>(1..1=
00_000).each{|x|arr &lt;&lt; x if try1(x)}<br>p arr #&gt; [1, 9, 45, 55, 99=
, 297, 703, 999, 2223, 2728, 4879, 4950, 5050, 5292, 7272, 7777, 9999, 1734=
4, 22222, 38962, 77778, 82656, 95121, 99999]<br>
<br><br><br></div>Harry<br><br></div>

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